Forces and Motion 1
A push or pull
Force
Is motion potential or kinetic energy?
Kinetic
What makes a bridge strong?
Pillars or arches
Stefan pushes a cart with three books so it reaches the end of a track. He puts six books onto the cart. What must he use next time so the cart reaches the end of the track?
a. less force
b. more force
c. the same force
d. a different cart
B. more force
A change in position is called
Motion
What causes an object to move?
Unbalanced force
Forces that cause a change in motion are called..
unbalanced forces
Friction in the air is called...
Air Resistance
Energy can be destroyed
TRUE or FALSE
FALSE
A large rock is motionless on a flat sidewalk. Which statement best explains why the rock remains motionless?
A) There are no forces acting on the rock.
B)The only force acting on the rock is directed toward the sidewalk.
C) The forces acting on the rock are all balanced
D) The sidewalk exerts an unbalanced force on the rock.
C
A force between two surfaces which prevents them from sliding past one another. A force that acts in the opposite direction of the traveling object
Friction
Student A is pushing a box with a force of 20N to the right. Student B is pushing with a force of 25 N to the left. What is the net force of this situation
5 N to the left
In a game of tug-o-war, what happens when the forces exerted by Team A and Team B are balanced?
neither team wins
Forces have___________________
Strength and direction
Why is it hard to win a tug-of-war against teachers?
Teachers have a lot of friction
An object that is accelerating can be
described as a(n) _____________ force.
Unbalanced
Forces on an object that are equal in size and opposite in direction, cancelling each other out are called...
Balanced Forces
As motion increases friction ________.
decreases
Why would an object in a spacecraft float in air rather than fall to the floor?
a. There is no gravity in space.
b. None of Newton's Laws of Motion applies to space.
c. The force of gravity in space is less than it is on Earth.
d. Inertia allows the object to overcome the force of gravity.
c. The force of gravity in space is less than it is on Earth.
What is the Law of Conservation of Energy
Energy cannot be created nor destroyed. Just transformed
What caused the watermelon to burst?
The force of the rubber bands was greater than the force of the watermelon.
Sandpaper sliders don't slide very fast because_____
Sandpaper creates a lot of friction.
Danielle pulled gently on a spring scale. The scale showed a force, but the block did not move. Why not?
a. The force that she applied was balanced by another force.
b. The string between the spring scale and the block was not strong enough.
c. The spring scale was broken, so there was no force when she pulled on it.
d. There was not enough friction for the block to move.
a. The force that she applied was balanced by another force.
Which of the following objects will have the greatest change in motion?
a. a small force applied to an object with a large mass.
b. a small force applies to an object with a small mass.
c. a large force applied to an object with a large mass.
d. a large force applied to an object with a small mass.
d. a large force applied to an object with a small mass.