When the net force of opposite forces is zero, the forces are
Responses
A unbalancedunbalanced
B unequalunequal
C not evennot even
D balanced
D balanced
Which situation is the BEST example of inertia?
Responses
A An old lady uses a walker and is able to cross the street.An old lady uses a walker and is able to cross the street.
B You go down a steep roller coaster and it feels like your stomach is going up into your throat.You go down a steep roller coaster and it feels like your stomach is going up into your throat.
C A rocket thrusts its boosters and lifts off the launching pad.A rocket thrusts its boosters and lifts off the launching pad.
D A rock is thrown vertically up in the air and it falls back to the earth.
D A rock is thrown vertically up in the air and it falls back to the earth.
In which situation is the speed of the car constant while its velocity is changing?
Responses
A The car travels down a straight track at 30 ms
.The car travels down a straight track at 30 m s .
B The car travels around a circular track at 30 ms
.The car travels around a circular track at 30 m s .
C The car begins traveling at 30 ms
and slows to 15 ms
.The car begins traveling at 30 m s and slows to 15 m s .
D The car begins from rest and accelerates to 20 ms
.
B The car travels around a circular track at 30 m/s.
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Question
Newton's second law can be expressed as a mathematical formula for the amount of force needed to accelerate an object. It is that force equals mass times acceleration, or, F=ma.
James is trying to prove Newton's 2nd law of motion. He tries to move four different objects with different masses, shapes, and sizes from point A to point B. The objects are a toy car, a car, a refrigerator, and a kitchen table. After some experimentation, he finds that force is dependent on the mass of the object, rather than it's size or shape. The object that takes the most force to move is the
Responses
A
B
C
D
D. Kitchen table.
Sally and Sue took a canoe trip down the Mississippi River. Their average speed for the trip south was 20 miles/hour. 20 miles/hour south is the girls'
Responses
A velocity.velocity.
B acceleration.acceleration.
C distance.distance.
D speed.
D. speed.
If the same amount of force were applied to all four balls in the picture, which would have the smallest change in its motion?
Responses
A 40kg40kg
B 5kg5kg
C 20kg20kg
D 10kg