All AP Physics 1 Resources
Example Questions
Example Question #81 :Newtonian Mechanics
What is the mass of a bowling ball that maintains an average kinetic energy ofwhile traveling at?
For this question we will use the kinetic energy equation.
Plug in and solve for the mass of the bowling ball.
The mass of the bowling ball is.
Example Question #82 :Newtonian Mechanics
A child weighing in anis walking at. What is his or her average kinetic energy?
For this question use the equation for kinetic energy.
Plug in and solve for the the kinetic energy.
The child will have a kinetic energy equal to.
Example Question #83 :Newtonian Mechanics
A box of massis initially at rest, and is then subject toof a directing horizontal pulling force. Neglecting friction and air resistance, what is the kinetic energy of the box after?
First, solve for the acceleration of the box using Newton's second law.
Plug in and solve for the acceleration.
Now use a kinematic equation to solve for the final velocity.
Plug in and solve for the final velocity.
Finally, we will use the kinetic energy equation to determine the kinetic energy of the box after.
Plug in and solve for the kinetic energy.
The final kinetic energy of the box will be.
Example Question #84 :Newtonian Mechanics
Two space ships are racing deep in space. At, Spaceship A is at the origin while traveling at. It is coasting, with it’s rockets off. Spaceship B is at. It’s traveling at. It’s rockets are firing with a constant force of. Both rockets have a mass of.
What is the total kinetic energy of the two spaceships at?
None of these
Finding net velocity of Spaceship:
Finding net velocity of Spaceship:
Example Question #85 :Newtonian Mechanics
Moment of inertia of disk:
A car with wheels of massand wheels of radiusis traveling at. Treating the wheels as disks of uniform mass density, calculate the rotational kinetic energy of one wheel.
None of these
Finding angular velocity:
Using
and
Combining equations and plugging in values:
Example Question #86 :Newtonian Mechanics
A soccer ball at rest of massis accelerated atfor. What is the final kinetic energy in Joules of the ball after?
None of these
First find the final speed of the ball using. Then, useto find the kinetic energy after 9s.
Example Question #87 :Newtonian Mechanics
Amissile has a net propulsion force of. Over a brief period, the missile speeds up uniformly from an initial velocityto. Assume that the missile will not lose mass during fuel consumption and so the net propulsion remains constant. What is the net work done on the rocket in kilojoules?
Find the KE of the missile at each velocity. The difference or change in KE is the net work done on the missile.
Divide by 1000 to convert to.
例子问题# 88:Newtonian Mechanics
A bullet with masshits the bullseye at. Assuming no loss of energy due to heat or frictional forces, how much energy in Joules did the bullet transfer to the target?
Find the kinetic energy:
Example Question #89 :Newtonian Mechanics
A sledder of massis traveling down a hill with slope ofabove the horizontal. If the sledder starts from rest and has an average frictional force of, what is the velocity of the sledder after travelingalong the slope?
我们可以开始with the expression for conservation of energy for this problem:
We are told that the sledder begins from rest, so we can eliminate initial kinetic energy. Also, if we say that the final height of the sledder is 0, we can eliminate final potential energy. Also, the only work being done is from friction, and the work is being removed from the system, so it will be negative. Therefore, we get:
Substituting in expressions for each of these, we get:
Rearranging for final velocity:
Now we just need an expression for initial height:
Plugging this in, we get:
We have all of these values, so time to plug and chug:
Example Question #90 :Newtonian Mechanics
The following train car has just went around the loop of this roller coaster and is now travelling to the left. The train car weighsand is travelling at a speed of.
What is the approximate kinetic energy of the train car?
Kinetic energy is defined by the following equation:
whereis mass, andis velocity.
In this question, you are given the mass and velocity, so by plugging in the given values it is possible to find the kinetic energy (in Joules).