21 questions
Which law of motion involves action and reaction forces?
1st Law
2nd Law
3rd Law
Texting in class = phone removal for the day
The attraction of a person's body toward Earth is called weight. The reaction force is
Earth pushing against the person
The person's body pushing against the Earth
the person's body pulling on the Earth
Which has the largest momentum?
Large truck parked at a rest stop.
Person walking on a sidewalk
Dog running across a street
Pickup truck speeding along a highway
The impulse-momentum relationship comes from
Newton's 4th Law
Newton's 2nd Law
Newton's 3rd Law
Newton's 1st Law
When you are in the way of a fast-moving object and can't get out of the way in time, there will be a smaller force of impact if you decrease its momentum over a
long time
short time
Padded dashboards in cars are safer in an accident than nonpadded ones because a passenger hitting the dashboard has
increased momentum
increased time of impact
decreased impulse
decreased time of impact
An astronaut floating alone in space throws a baseball. If the ball floats away at a speed of 20 m/s, the astronaut will
move at a higher speed in the opposite direction
move at a lower speed in the opposite direction
move in the opposite direction at a speed of 20 m/s
If you push an object twice as far using the same force, you do
4 times the work
Half the work
2 times the work
the same amount of work since the force is the same
A person walks slowly up the stairs. Later the same person runs quickly up the stairs. Both jobs involve the same work, but different amounts of _______________.
power
energy
both power and energy
strength
An object that has kinetic energy must be
in an elevated position
falling
at rest
moving
When a car applies its brakes, the kinetic energy is transformed into
potential energy
heat
kinetic energy
wind energy
A ball rolling down an incline has its maximum speed at
the top
the exact middle
the bottom
difficult to predict without knowing the slope of the incline
Which of the following is an example of NO Work being done
Pushing a coffee mug across a counter.
Picking up a bowling ball from the ground.
Bowling ball travelling at constant speed
Car driving down in incline.
a 10 kg mass is suspended 5 meters above the ground. What is its potential energy with respect to the ground?
50 J
500 J
5 J
Which has the largest kinetic energy?
Car travelling at 30 km/hr
Same car travelling at 60 km/hr
Both have the same energy since the cars have the same mass.
none of the above
A moving object has
velocity
momentum
energy
all of these
Horses on a merry-go-round move at the slowest speed if they are
near the middle
near the outside
They all rotate at the same speed
The rotational inertia of your leg is greater when your leg is
straight
bent
Toss a stick in the air, and it will rotate around its
heavier end
geometric center
center of mass
The Leaning Tower of Pisa doesn't fall over because its center of gravity is
relatively low for such a tall building
above a place of support
stabilized by its structure
A car travels in a circle with constant speed. The net force on the car is
zero because the car is not accelerating
in the direction of travel
directed toward the center of the curve