Question

1. on the first blank line, state what type of force is illustrated in the picture (tension, friction, elastic, gravitational, electrostatic, magnetic). on the second blank line, state whether it is a contact force or an action - at - a - distance force.

read the statements given below. if the statement is true, write \t\ on the line in front of the statement. if it is false, write \f\ and rewrite the statement to make it true.

1. a force cannot set a motionless object in motion.
2. a force can make a moving object change direction.
3. a force can change the shape of an object.
4. tension force slows down or stops motion due to surfaces rubbing against each other.
5. elastic force pulls objects toward each other.
6. an example of magnetic force is lightning.

Explanation:

Step1: Analyze trampoline picture

The force exerted by the trampoline on the person is elastic force as the trampoline sags and then pushes back. It is a contact force as the person is in contact with the trampoline.

Step2: Analyze lightning picture

The force associated with lightning is electrostatic force. It is an action - at - a - distance force as it acts without direct contact.

Step3: Analyze parachute picture

The force on the parachute is tension force from the ropes holding it. It is a contact force as the ropes are in contact with the parachute and the person.

Step4: Analyze magnet picture

The force is magnetic force. It is an action - at - a - distance force as the magnet attracts objects without direct contact.

Step5: Analyze statement 8

A force can set a motionless object in motion according to Newton's first law. So the statement is false. The corrected statement is: A force can set a motionless object in motion.

Step6: Analyze statement 9

A force can change the direction of a moving object as per Newton's laws. So the statement is true.

Step7: Analyze statement 10

A force can change the shape of an object. For example, squeezing a sponge. So the statement is true.

Step8: Analyze statement 11

Friction force slows down or stops motion due to surfaces rubbing against each other, not tension force. So the statement is false. The corrected statement is: Friction force slows down or stops motion due to surfaces rubbing against each other.

Step9: Analyze statement 12

Gravitational force pulls objects toward each other, not elastic force. Elastic force is a restoring force when an object is deformed. So the statement is false. The corrected statement is: Gravitational force pulls objects toward each other.

Step10: Analyze statement 13

Lightning is an example of electrostatic force, not magnetic force. So the statement is false. The corrected statement is: An example of electrostatic force is lightning.

Answer:

Trampoline: Elastic, Contact
Lightning: Electrostatic, Action - at - a - distance
Parachute: Tension, Contact
Magnet: Magnetic, Action - at - a - distance

1. F, A force can set a motionless object in motion.
2. T
3. T
4. F, Friction force slows down or stops motion due to surfaces rubbing against each other.
5. F, Gravitational force pulls objects toward each other.
6. F, An example of electrostatic force is lightning.