Show:
incline plane
wedge
wheel and axel
screw
lever
100
A solid object that changes its position over time is best described in which way? changing motion changing color changing density changing temperature
changing motion
100
force
Which is a push or pull that acts on an object called? force speed inertia momentum
100
Earth rotates around the sun.
Which statement proves that Earth is affected by the pull of gravity? Earth’s water has a cycle. Earth rotates around the sun. Earth is shaped like a sphere. Earth has mountains and valleys.
100
Which is the best example of unbalanced forces acting on an object? a boy sitting on a chair a dog holding a ball in its mouth a girl jumping off her skateboard a marble rolling at constant speed
a girl jumping off her skateboard
100
Which do levers have to overcome to do work? gravity momentum air resistance inclined plane
gravity
200
A woman on a bicycle traveled 15 miles in one hour. During the next hour, she traveled another 18 miles. Which best describes the motion of the bicycle during the first hour? faster than the second hour slower than the second hour about the same as the second hour exactly the same as the second hour
slower than the second hour
200
There is no acceleration
When two equal and opposite forces are at work, what happens to acceleration? It increases. It decreases. There is no acceleration. There is maximum acceleration.
200
lift
Which type of force is being applied to someone on a swing to make him or her move through the air? lift pull drag friction
200
The force striking the ball must be less than the force of gravity.
What must be true for a baseball to be hit high into the air? The force striking the ball must be greater than the force of gravity. The force striking the ball must be less than the force of gravity. The force striking the ball must be equal to the force of gravity. The ball’s ability to change direction must overcome force of gravity.
200
Which best describes a person pushing on a brick wall and the wall not moving? balanced forces frictional forces gravitational forces unbalanced forces
unbalanced forces
300
To determine the speed of an object, what information should be known? time and height distance and time distance and inertia height and distance
distance and time
300
The heavier car will travel a shorter distance because it has more mass.
Two cars are pushed equally. Will the heavier car travel a longer or shorter distance than the lighter car? The heavier car will travel a longer distance because it has more mass. The heavier car will travel a shorter distance because it has more mass. The heavier car will travel a longer distance because it has more thrust. The heavier car will travel a shorter distance because it has more thrust.
300
to produce electricity
Wind can be used as an energy resource to operate machines. Which is one way wind is useful? to control flooding to produce electricity to purify drinking water to move water from the ocean
300
It is acted upon by an unbalanced force.
An object at rest remains at rest until what happens? Its density increases. It has a change of mass. It is acted upon by heat. It is acted upon by an unbalanced force.
300
Which will happen to an object that has unbalanced forces acting on it? It will change speed. It will remain still. It will increase in mass. It will decrease in mass.
It will change speed.
400
exactly the same as the first hour
A helicopter traveled 200 miles in one hour. During the next hour, it traveled another 200 miles. Which best describes the average speed of the helicopter during the second hour? faster than the first hour slower than the first hour about the same as the first hour exactly the same as the first hour
400
mass and force
Acceleration of an object depends on which two factors? mass and force mass and weight motion and gravity inertia and gravity
400
a windmill
Which machine is powered by wind? a flag a blender a windmill an airplane
400
unbalanced forces
Which must be present to make things change movement and direction? equal forces zero forces opposite forces unbalanced forces
400
An object is moving at a steady speed. What will happen if additional force is applied to the object in the same direction in which the object is moving? The object will stop. The object will change direction. The object’s speed will decrease. The object’s speed will increase.
. The object’s speed will increase.
500
the distance and time traveled by the object
What is necessary to determine the speed of an object? the shape and color of the object the mass and volume of the object the melting and boiling point of the object the distance and time traveled by the object
500
distance traveled divided by time it took to travel
How can the velocity of an object best be determined? distance traveled divided by time it took to travel time it took to travel divided by distance traveled distance traveled divided by speed traveled speed traveled divided by distance traveled
500
gravity
Water flowing over a dam is sometimes used to make a machine produce electricity. What causes the water to flow over the dam? gravity momentum balanced forces frictional forces
500
In an experiment, a toy car is placed on a racing track. The toy car is pushed and the speed is recorded. Which step of the experiment best illustrates balanced forces acting upon the car? the car being placed on the track the car sitting on the track the car being pushed on the track the car slowing down on the track
the car sitting on the track
500
A long round balloon with a cone tip is fastened to the end of a toy rocket. When the balloon is blown up and let go, it shoots the rocket into the air. What is the unbalanced force in this example? the pull of gravity the weight of the rocket the volume of the balloon the air escaping the balloon
the air escaping the balloon