Unit 1 test physics
The same
Compared to the mass of a certain object on earth, the mass of the same object on the moon is
follow a straight-line path
Whirl a rock horizontally at the end of a string and it follows a circular path. If the string breaks, the tendency of the rock is to:
All of these
Your weight is:
less than the speed it had when thrown upwards
A ball is thrown upwards and caught when it comes back down. In the presence of air resistance, the speed with which it is caught is always:
directed downward
A ball tossed upward rises, reaches its highest point, and then falls back to its starting point. During this time the acceleration of the ball is always:
Zero
A car maintains a constant velocity of 100 km/hr for 10 seconds. During this interval it's acceleration is:
Magnitude and direction
A force is a vector quantity because it has both
Increases
A heavy block at rest is suspended by a vertical rope. When the block is accelerated upward by the rope, the rope tension
Zero
A hockey puck is set in motion across a frozen pond. If ice friction and air resistance are neglected, the force required to keep the puck sliding at velocity is:
Mass
A kilogram is a measure of an objects
About 20 m/s
A package falls off a truck that is moving at 20 m/s. Neglecting air resistance, the horizontal speed of the package just before it hits the ground is:
the milk carton has inertia
A sheet of paper can be withdrawn from under a container of milk without toppling it if the paper is jerked quickly. This best demonstrates that
exactly below the midpoint of the ceiling
A truck is moving at constant velocity. Inside the storage compartment, a rock is dropped from the midpoint of the ceiling and strikes the floor below. The rock hits the floor
always have forces that oppose their motion
According to Newton's law of inertia, a railroad train in motion should continue going forever even if its engine is turned off. We never observe this because railroad trains
1N
An apple at rest weighs 1N. The net force on the apple when it's in free fall is
0N
An apple weighs 1 N. When held at rest above your head, the net force on the apple is
Twice as much
An object is propelled along a straight-line path by a force. If the net force were doubled, the object's acceleration would be
60 m/s
At one instant a heavy object in air is moving upward at 50 meters per second. One second later it's speed is approximately:
is exactly equal in magnitude
For an action force, there must be a reaction force that
Push harder on the ground
How could the apple achieve greater acceleration
10 m/s
If a freely falling object were somehow equipped with a speedometer, its speed reading would increase each second by about
1 second
If a projectile is fired straight up at a speed of 10 m/s, the time it takes to reach the top of its path is about
change by the same amount each second
If an object moves with constant acceleration, its velocity must
continue moving at the same velocity
If no external forces are acting on a moving object, it will
Inertia
If one object has twice as much mass as another object, it also has twice as much
The orange would move forward but the apple would move backwards
If the apple were to pull the orange while on roller skates instead of on firm ground
The ground (through friction) opposing the oranges motion
If the apple were to stop pulling suddenly, the apple would come to a stop. The net force accomplishing this deceleration is
They would accelerate more slowly
If the orange were heavier and all other things remained the same
10 meters per second per second
If you drop an object, it will accelerate downward at a rate of 10 meters per second per second. If you instead throw it downwards, it's acceleration (in the absence of air resistance) will be:
greater than zero
In the above picture, the orange is being accelerated forward by the apple over a surface which is not frictionless. The orange and the apple move together. The net force on the orange is
Two
In the horizontal direction, there are how many forces acting on the apple
Two
In the horizontal direction, there are how many forces acting on the orange
Greater
In the third picture above, the strong man is tied to two horses pulling in one direction, and to a tree. Compared to the 2nd picture, the tension that the strong mans body has to withstand is
moon
In which case would you have the largest mass of gold?
Neither- they will both hit the same speed
Someone standing at the edge of a cliff throws one ball straight up and another ball straight down at the same initial speed. Neglecting air resistance, the ball to hit the ground below the cliff with the greater speed will be:
continues at the speed it had when it encountered the second force
Suppose a particle is being accelerated through space by a 10 N force. Suddenly the particle encounters a second force of 10 N in the opposite direction from the first force. The particle with both forces acting on it
Newton's second law
The answer to the previous question follows most directly from
being accelerated forward
The apple is
30N
The force of friction on a sliding object is 30 N. The applied force needed to maintain a constant velocity is:
The apple is pulling the orange
The most direct cause of the orange being accelerated forward is
Positive
The net force on the system comprised of the apple and the orange is
The ground pushing forward on the apple minus the ground pulling back on the orange (external forces)
The net force on the system compromised of the apple and the orange is equal to
Equal and opposite
The vertical forces on the orange & apple are
4 M
Two people, one twice as massive as the other, attempt a tug-of-war with 12 meters of massless rope on frictionless ice. After a brief time, they meet. The heavier person slides a distance of
Velocity is zero and it's acceleration is about 10 meters per second per second
When a rock is thrown straight upwards gets to the exact top of its path, it's
no longer accelerates
When a rocket ship accelerating in outer space runs out of fuel, it
Add up to your equal weight
When you stand at rest on a pair of bathroom scales, the readings on the scales will always:
zero
Whenever the net force on an object is zero, it's linear acceleration
all of these
Which of the following may be true of an object in mechanical equilibrium
none of the above
While a car travels around a circular track at a constant speed, its
velocity increases
While an object near the Earth's surface is in free fall, its
