A rocket blasts off and moves straight upward from the launch pad with
constant acceleration. After 3.0 seconds the rocket is at a height of 77
meters. What is the rocket's velocity at that time?
The maximum energy a bone can absorb without breaking is surprisingly small. For a healthy human of mass 59 kg , experimental data show that the leg bones can absorb about 200 J . Part A From what maximum height could a person jump and land rigidly upright on both feet without breaking his legs
Answer:
0.35mExplanation:
In this problem we want to solve for the height given the potential energy
the potential energy is the energy possessed by a body by virtual of it position.
given data
mass m=59kg
PE(potential energy)= 200J
Height h=?
assuming g=9.81,/s^2
we know that the expression for potential energy is
PE=mgh
substituting we have
200=59*9.81*h
200=578.79h
divide both sides by 578.79
h=200/578.79
h=0.35m
Therefore the height is 0.35m
Aballisprojectedverticallyupwardswithaninitialvelocityofugoestoa
maximumheighthbeforecomingtoground.Whatisthevalueofh?
which of the following statements about mass and weight is correct?
A. "Mass" is the scientific term for "weight''
B. Weight directly measures force while mass directly measures amount of matter.
C. Weight has unit of kilograms or grams. Mass has unit of newtons.
D. The mass of an object depends on the size of the object. The weight of an object dosent depend on the size of the object.
The correct answer is B. Weight directly measures force while mass directly measures the amount of matter.
Explanation:
Weight and mass are two related but not identical concepts. The first term "mass" can be found by measuring the amount of matter in a body or substance. For example, the mass in an apple is around 80 grams depending on its size. In this context, mass is measured using units such as grams or kilograms. On the other hand, weight considers not only the matter in an object but the force exerted in it, especially, the gravitational force. In the case of the apple, the weight is 1 N as newtons (N) are used to measure force and this is the result of multiplying the mass by gravity. According to this, option B is correct.
Carmen is helping load furniture and boxes onto a moving truck. She picks up boxes of her things, places them on a cart, and pushes the cart to the moving van. Which term best describes the type of force Carmen uses?
A. contact
B. friction
C. gravity (this one is wrong)
D. noncontact(this one is wrong)
A car accelerates in the +x direction from rest with a constant acceleration of a1 = 1.89 m/s^2 for t1 = 20 s. At that point the driver notices a tree limb that has fallen on the road and brakes hard for t2 s until it comes to a stop. Required:a. Write an expression for the car's speed just before the driver begins braking, v1.b. If the limb is on the road at a distance of 550 meters from where the car began its initial acceleration, will the car hit the limb?c. How far, in meters, from the original location of the limb will the car be when it stops?
Answer:
A.) 37.8 m/s
B.) No
C.) 172 m
Explanation:
Given that car accelerates in the +x direction from rest with a constant acceleration of a1 = 1.89 m/s^2 for t1 = 20 s. At that point the driver notices a tree limb that has fallen on the road and brakes hard for t2 s until it comes to a stop. Required:
a.) Write an expression for the car's speed just before the driver begins braking, v1.
Since the car accelerate from rest, initial velocity U = 0
Using first equation of motion
V1 = U + at
V1 = 1.89 × 20
V1 = 37.8 m/s
b.) If the limb is on the road at a distance of 550 meters from where the car began its initial acceleration, will the car hit the limb?
Using third equation of motion
V^2 = U^2 + 2as
37.8^2 = 0 + 2 × 1.89 × S
1428.84 = 3.78S
S = 1428.84 / 3.78
S = 378m
Since the limb is on the road at a distance of 550 meters from where the car began its initial acceleration, we can therefore conclude that the car will not hit the limb.
c. How far, in meters, from the original location of the limb will the car be when it stops?
550 - 378 = 172 m
The car will be 172 metres from the limb.
Which of the following statements is true?
Anemia can be avoided by eating a diet rich in calcium.
CAT scans use powerful magnets and radio signals to view the inside of the body.
X-rays are only useful for viewing broken bones.
Exercise can reduce pain, relieve stress, and increase energy.
Answer:
c
Explanation:
Answer:
Exercise can reduce pain, relieve stress, and increase energy.Explanation:
What value resistor will discharge a 2.60 μFμF capacitor to 20.0%% of its initial charge in 2.20 msms ? nothing Ω
Answer:
The value of resistor is 525.76 ohms
Explanation:
Given;
capacitance, C = 2.6 μF = 2.6 x 10⁻⁶ F
let the initial charge on the capacitor = Q₀
time , t = 2.2 ms = 2.2 x 10⁻³ s
The discharge of the capacitor is given by;
[tex]Q(t) = Q_oe^{-\frac{t}{RC} }[/tex]
Where;
Q(t) is the charge after 2.2ms = 20% of Q₀ = 0.2Q₀
[tex]Q(t) = Q_oe^{-\frac{t}{RC} }\\\\0.2Q_o = Q_oe^{-\frac{t}{RC} }\\\\0.2 = e^{-\frac{t}{RC} }\\\\ln(0.2) = -\frac{t}{RC}\\\\-1.6094 = -\frac{t}{RC}\\\\R = \frac{t}{1.6094C} \\\\R = \frac{2.2*10^{-3}}{1.6094*2.6*10^{-6}}\\\\R = 525.76 \ ohms[/tex]
Therefore, the value of resistor is 525.76 ohms
Two sailors, Popped-Eye and Mack Sparrow, are using identical pulleys to lift sunken treasure to their ship. Popped-Eye's treasure is three times heavier than Mack Sparrow's. Each sailor lifts his treasure an identical distance. Popped-Eye lifts his treasure the entire distance in 30s. Mack Sparrow requires twice as much time.
Which statement below is true regarding Popped-Eye's and Mack Sparrow's relative power?
A) Their power is equal.
B) Popped-Eye is 3 times more powerful than Mack Sparrow.
C) Popped-Eye is 6 times more powerful than Mack Sparrow.
D) Popped-Eye is 1.5 times more powerful than Mack Sparrow.
Answer:
Popped-Eye is 3 times more powerful than Mack Sparrow.
Explanation:
Popped-Eye is 6 times more powerful than Mack Sparrow.
What is power?In science and engineering, power is the rate at which work is completed or energy is delivered. It can be expressed as the product of the work completed (W) or the energy transferred (E) divided by the time interval (t), or W/t.
Given parameters:
Popped-Eye's treasure is three times heavier than Mack Sparrow's.
Mack Sparrow requires twice as much time.
So, Popped-Eye can lift times heavier treasure in half of time compere to Mack Sparrow .
Hence, Popped-Eye's power is 3÷(1/2) = 3×2 = 6 times more than Mack Sparrow's.
Learn more about power here:
https://brainly.com/question/12127373
#SPJ2
What is the answer to this question?
Answer:
C I just did it. so yeah....
A nearby highway is being designed for traffic whose speed limit is 90km/h. If most people become uncomfortable on banked curve larger than 45 degrees, what is the minimum radius you could design the curve
Answer:
The minimum radius of the curve is 6125 m
Explanation:
Given;
speed limit of the highway, V = 90 km/h = 25 m/s
banking angle, θ = 45°
The minimum radius of the curve will be calculated by applying banking angle formula;
[tex]mg tan \theta = F_{centripetal \ force}\\\\mg tan \theta = \frac{mv^2}{r}\\\\ g tan \theta = \frac{v^2}{r}\\\\r = \frac{v^2}{ g tan \theta}\\\\r = \frac{(25)^2}{(9.8)(1)} \\\\r = 6125 \ m[/tex]
Therefore, the minimum radius of the curve is 6125 m
two forces act on a 6 kg object. one of the forces is 10 N. if the object accelerates at 2 m/s^2, what is the greatest possible magnitude of the other force
Answer:
22NExplanation:
Let the two forces be acting in the horizontal direction on the object.
Given
Mass m = 6kg
One of the force = 10N
acceleration = 2m/s²
Taking the sum of forces along the x component, we will have:
[tex]\sum F_x = ma_x\\Ff - 10 = 6(2)\\Ff - 10 = 12\\Ff = 12+10\\Ff = 22N[/tex]
Note that Ff is the greatest possible magnitude of the other force.
Hence the greatest possible magnitude of the other force is 22N
Choose all the right answers.
Each new cell produced by mitosis:
is different
inherits all the traits from its parent
obtains new traits
is identical to the parent's structure
Answer:
B and D
Explanation:
Answer:
It is B. inherits all the traits from its parent
And D. is identical to the parent's structure
Explanation:
Hope this helped have an amazing day!
PLEASE HELP
You finally got inside the school. You look outside and see the zombie still coming after you. He is walking at 0.5 m/s. How long will it take him to get to the school if he is 200 m away?
Answer:
400 seconds
Explanation:
Divide the total distance by the unit rate
200/0.5 = 400
400 seconds
Answer:
400 seconds
Explanation:
why is the unit of power called derived unit
Answer:The ampere is unique in that it uses the base unit of time (t) in its definition (second). All other electrical and magnetic units (such as voltage, power, and magnetic flux) use various combinations of base units in their definitions and are called derived units.
Explanation:
In hookes law an exact law of physics or an approximation? Why?
A space vehicle is traveling at 4140 km/h relative to Earth when the exhausted rocket motor is disengaged and sent backward. The relative speed between the motor and the command module is then 99 km/h. The mass of the motor is four times the mass of the module. What is the speed of the command module relative to Earth just after the separation
Answer:
V_ce = 1128 m/s
Explanation:
We are given;
Speed of space vehicle relative to the earth; V_i = 4140 km/h = 1150 m/s
relative speed between the motor and the command module; V_mc = 99 km/h = 27.5 m/s
mass of the motor is four times the mass of the module.
If the mass of the module is m
Mass of motor = 4m
From conservation of momentum, since the system is isolated, then;
Initial momentum = final momentum.
Thus;
MV_i = 4m(V_me) + m(V_ce) - - - (eq 1)
Where;
M is mass of space vehicle
V_me is speed of motor relative to the earth
V_ce is speed of command module relative to the earth
Now, relative speed between the motor and the command module is given by the formula;
V_mc = V_me - V_ce
Thus, V_me = V_mc + V_ce
Putting (V_mc + V_ce) for V_me in eq 1, we have;
MV_i = 4m(V_mc + V_ce) + m(V_ce)
Now, the mass of the space vehicle will be the sum of the mass of the module and mass of the motor.
Thus;
M = m + 4m
M = 5m
Thus;
5mV_i = 4m(V_mc + V_ce) + m(V_ce)
Divide through by m to get;
5V_i = 4(V_mc + V_ce) + (V_ce)
5V_i = 4V_mc + 4V_ce + V_ce
5V_i = 4V_mc + 5V_ce
We want to find the speed of the command module relative to Earth just after the separation. Thus, let's make V_ce the subject;
V_ce = (5V_i - 4V_mc)/5
V_ce = ((5 × 1150) - (4 × 27.5))/5
V_ce = 1128 m/s
The first stage of a Saturn V space vehicle consumed fuel and oxidizer at the rate of 1.50 3 104 kg/s with an exhaust speed of 2.60 3 103 m/s. (a) Calculate the thrust produced by this engine. (b) Find the acceleration the vehicle had just as it lifted off the launch
Answer:
Explanation:
Thrust produced = v dm / dt
v is speed of exhaust and dm / dt is rate at which mass of gas is being thrown out .
= 2.603 x 10³ x 1.503 x 10⁴
= 3.91 x 10⁷ N ,
What is the magnitude of the upward thrust force (assumed constant)?Express your answer with the appropriate units
Complete Question
A helicopter of mass [tex]1.40 *10^{3}[/tex] kg is descending vertically at 3.00 m/s. The pilot increases the upward thrust provided by the main rotor so that the vertical speed decreases to 0.450 m/s as the helicopter descends 5.00 m. What is the magnitude of the upward thrust force (assumed constant)?Express your answer with the appropriate units.
Answer:
The value is [tex]F = 11257 \ N[/tex]
Explanation:
From the question we are told that
The mass of the helicopter is [tex]m = 1.40 *10^{3} \ kg[/tex]
The initial descending speed is [tex]u= 3.00 \ m/s[/tex]
The descending speed after the upward thrust has been increased is [tex]v = 0.450 \ m/s[/tex]
The height when descending speed is [tex]v = 0.450 \ m/s[/tex] is [tex]s = 5.0 \ m[/tex]
Generally according to the kinematics equations
[tex]v^2 = u^2 + 2(a)s[/tex]
Here a is the acceleration due to gravity plus the acceleration of the helicopter
So
a = [tex]a = -g + a_h[/tex]
the negative sign is due to the fact that the direction of the plane is in the negative y axis
So
[tex]v^2 = u^2 + 2(-g + a_h)s[/tex]
=> [tex]0.45^2 = 3^2 + 2(-9.9 + a_h) * 5[/tex]
=> [tex]a_h = \frac{-8.7975}{5} + 9.8[/tex]
=> [tex]a_h = 8.0405 \ m/s^2[/tex]
Generally the thrust force is mathematically represented as
[tex]F = m * a_h[/tex]
=> [tex]F = 1.40 *10^{3} * 8.0405[/tex]
=> [tex]F = 11257 \ N[/tex]
Which picture shows an example of no work being done?
B, Its the one with the kid trying to lift a weight.
Explanation:
Got it right Edge 2020.
Answer:
it's the weights kid!!! the other user got it thank them, i got it right bc of them :)
Explanation:
Which would increase the speed of a sound wave?
O A wave passes from a solid to a liquid while remaining the same temperature.
O The medium increases in temperature while remaining in the same phase.
O The medium decreases in temperature while remaining in the same phase.
O A wave passes from a liquid to a gas while remaining the same temperature.
(First correct answer with explanation gets Brainliest)
Answer:
B. The medium increases in temperature while remaining in the same phase.
Explanation: The most important factor influencing the speed of sound in air is temperature. The speed is proportional to the square root of the absolute temperature, giving an increase. Due to this information, B is the best answer.
How fast would a 4.75 cm copper bar have to move at right angles to a 0.700 T magnetic field to generate 1.50 V (the same as a AA battery) across its ends
Answer:
ω = 1899.5 radian / s
Explanation:
EMF induced by a rotating rod = 1 /2 B ω L² where ω is angular velocity of rod and L is its length . B is magnetic field
1 /2 B ω L² = 1.5
1/2 x .7 x ω x .0475² = 1.5
ω = 1899.5 radian / s
A dentist causes the bit of a high-speed drill to accelerate from an angular speed of 1.34 x 104 rad/s to an angular speed of 4.37 x 104 rad/s. In the process, the bit turns through 3.10 x 104 rad. Assuming a constant angular acceleration, how long would it take the bit to reach its maximum speed of 7.43 x 104 rad/s, starting from rest?
Answer:
2.66 s
Explanation:
Given The initial angular speed ([tex]\omega_o[/tex]) = 1.34 x 10⁴ rad/s, the final angular speed (ω) = 4.37 x 10⁴ rad/s, the angular acceleration (α), distance (θ) = 3.10 x 10⁴ rad.
Using the formula:
[tex]\omega^2=\omega_o^2+2\alpha \theta\\\\Substituting:\\(4.37*10^4)^2=(1.34*10^4)^2+2(3.1*10^4)\alpha\\\\(4.37*10^4)^2-(1.34*10^4)^2=2(3.1*10^4)\alpha\\\\2(3.1*10^4)\alpha=1.73*10^9\\\\\alpha=2.79*10^4\ rad/s^2[/tex]
The constant acceleration = 2.79 * 10⁴ rad/s.
Since there is constant acceleration, to reach a final speed of 7.43 x 10⁴ rad/s, we use the formula:
[tex]\omega =\omega_o +\alpha t\\\\\omega_o=0,\omega=7.43*10^4\ rad/s,\alpha=2.79*10^4\ rad/s^2\\\\Substituting:\\\\7.43*10^4=0+2.79*10^4t\\\\7.43*10^4=2.79*10^4t\\\\t=2.66\ s[/tex]
how many hydrogen atoms are needed to bond with carbon so that both fulfill the octet rule?
Answer:5
Explanation:
5 right
Answer:
4
Explanation:
Carbon, with 4 electrons in its valence shell, will need another four electrons to fulfill the octet rule. Thus it needs to combine with 4 hydrogen atoms to form a stable compound called methane(CH4)
Police at a crime scene find a ceramic mug shattered on the sidewalk. They want to determine the window from which the mug fell, and they decide to make a model of the fall. Which quantitiy would be an important boundary condition for this model?
the hardness of the sidewalk where the mug landed
the time of day when the incident occurred
the final speed of the mug
the initial height of the mug above the sidewalk
Answer:
Initial height
Answer:
A: the hardness of the sidewalk where the mug landed
Explanation:
did the quick check
"The magnitude of the acceleration due to gravity on the surface of planet A is twice as great as on the surface of planet B. What is the ratio of the weight of mass X on the surface of planet A to its weight on the surface of planet B?"
Answer:
2 : 1
Explanation:
Given that The magnitude of the acceleration due to gravity on the surface of planet A is twice as great as on the surface of planet B. What is the ratio of the weight of mass X on the surface of planet A to its weight on the surface of planet B?"
Since the magnitude of the acceleration due to gravity on the surface of planet A is twice as great as on the surface of planet B. And
Weight W = mg
Mass is always constant
2g : g
The ratio of the weight of mass X on the surface of planet A to its weight on the surface of planet B will be:
2 : 1
If everything else remains the same, but the charges of two objects are each doubled, the electrostatic force between them will be __________ times what it was before.
Answer:
Four times
Explanation:
The electrostatic force between the two charges is given by :
[tex]F=\dfrac{kq_1q_2}{d^2}[/tex]
d is the distance between two charges
k is electrostatic constant
When both charges are doubled, [tex]q_1'=2q_1\ \text{and}\ q_2'=2q_2[/tex], new force is given by :
[tex]F'=\dfrac{kq_1'q_2'}{d^2}\\\\F'=\dfrac{k(2q_1)(2q_2)}{d^2}\\\\F'=4\times \dfrac{kq_1q_2}{d^2}\\\\F'=4F[/tex]
So, the electrostatic force between them will be four times what it was before.
A 1.95 m length of wire is held in an east–west direction and moves horizontally to the north with a speed of 15.5 m/s. The vertical component of Earth's magnetic field in this region is 40.0 μT directed downward. Calculate the induced emf between the ends of the wire and determine which end is positive.
Answer:
[tex]\epsilon=1.2\times 10^{-3}\ V[/tex]
Explanation:
Given that,
Length of a wire, l = 1.95 m
Speed of the wire, v = 15.5 m/s
The vertical component of Earth's magnetic field in this region is 40.0 μT directed downward.
We need to find the induced emf between the ends of the wire and determine which end is positive. The induced emf for a wire is given by :
[tex]\epsilon=Blv\\\\\epsilon = 40\times 10^{-6}\times 1.95\times 15.5\\\\\epsilon=1.2\times 10^{-3}\ V[/tex]
So, the induced emf between the ends of the wire is [tex]1.2\times 10^{-3}\ V[/tex].
CAN ANYONE PLEASE HELP ME WITH THIS QUESTION THAT IS ABOVE PLEASE I REALLY NEED THE HELP I AM STRUGGLING PLEASE THANK YOU IF YOU ANSWER MY QUESTION I APPRECIATE IT
Answer:
D.
Explanation:
Which of the following equipment is related to fencing?
A.
Sabre
B.
Bib
C.
Épée
D.
All of the above