Force, Motion, & Gravitation
The mass of an apple on the Moon is this much less than the mass of an apple on Earth.
What is no difference?
As an object falls freely, its magnitude of these two increase.
What are velocity and displacement?
This one of the following is not a scalar.
A. temperature
B. distance
C. mass
D. force
What is D. force?
This is when an object is in static equilibrium.
What is if the sum of external forces and the sum of external torques are zero.
What is the unit of momentum?
J*s/m
A sheet of paper can be withdrawn from under a milk carton without toppling the carton if the paper is jerked away quickly. This demonstrates that:
What is: The milk carton has enough inertia to remain in place.
A freely falling object on Earth, 10 s after starting from rest, has a speed of about:
100 m/s
Two identical balls (A and B) fall from rest from different heights to the ground. Ignoring air resistance, the ratio of the height from which A and B fall is ___ if ball B takes twice as long as ball A to reach the ground.
1:4
In order to balance a force in the north-east direction, what direction should another force be applied?
In the south-west direction
Angular momentum of a system is constant when...
When a 17 kg fish is weighed with two spring scales, the readings on the scales are...
The sum of the two scales is 34 kg
Starting from rest, it would take how long for a sports car to reach 60 mi/h, if it has an acceleration of 13.1 mi/hr?
4.6 s
Which direction is a car's acceleration in if a car is traveling to the North (+y direction) begins to slow down as it approaches a stop sign?
The acceleration of the car is negative.
What is it known as when a body experiences a slight tilt and then returns to its original position?
Stable equilibrium
The area under the curve of a force vs. time graph represents what?
Impulse
A block of mass m is resting on a 20 degree slope. The block has coefficients of friction equal to 0.55 and 0.45 with the surface. Block m is connected via a massless string over a massless, frictionless pulley to a hanging 2 kg block. The minimum mass of block m so that it doesn't slip is...
2.3 kg
An 8.7 hour trip is made at an average of 73 km/h. If the first third of the journey was driven at 96.5 km/h, the average speed for the rest of the trip is...
62 km/h
A bat hits a baseball, and the baseball's direction is completely reversed and its speed is doubled. If the actual time of contact with the bat is 0.45 s, the ratio of the acceleration to the original velocity is...
-6.7 s-1:1
Consider a winch that pulls a cart at constant speed up an incline. Point A is at the bottom of the incline and Point B is at the top. What is true about the kinetic and potential energy?
The kinetic energy of the cart is conserved.
What equation represents the kinetic energy for a car of mass m that is moving with momentum p?
p2/2m
A plastic ball in a liquid is acted upon by its weight and a buoyant force. The weight of the ball is 4.4 N. The buoyant force of 8.4 N acts vertically upward. An external force acting upon the ball maintains it in a state of rest. The external force is...
4 N, downward
21.4 m/s
A toy rocket is launched vertically from ground level where y=0 m, at time t=0 s. The rocket engine provides constant upward acceleration during the burn phase. At the instant of engine burnout, the rocket has risen to 64 m and acquired a velocity of 60 m/s. The rocket continues to rise in unpowered flight, reaches maximum height and then falls back to the ground. The upward acceleration of the rocket during the burn phase is...
28 m/s2
A uniform rod of mass M sticks out from a vertical wall and points toward the floor. The smaller angle it makes with the wall is theta, and the rod's end is attached to the ceiling by a string parallel to the wall. The tension in the supporting string is...
Mg/2
A 3.3 kg object moving at 6.9 m/s makes a perfectly inelastic collision with a 3.6 kg object that is initially at rest. The percentage of the initial kinetic energy of the system lost during the collision is...
What is 52%?