physics

Question 1

How do non-contact forces act?

Answer 1

Non-contact forces act between two objects that are not physically touching each other.

Question 2

How do contact forces act?

Answer 2

Contact forces are forces that act between two objects that are physically touching each other.

Question 3

How much momentum does a stationary object have?

Answer 3

It has zero momentum.

Question 4

What are two ways you can increase an objects momentum?

Answer 4

Increase its mass. Increase its speed.

Question 5

How do you stop a moving object?

Answer 5

Apply a force in the direction opposing its motion.

Question 6

What part of the object do non-contact forces act from?

Answer 6

Non-contact forces act from the centre of an object.

Question 7

What does the size of an arrow represent?

Answer 7

The size of the force.

Question 8

Name 3 non-contact forces

Answer 8

Magnetic force
Electrostatic force
Gravitational force

Question 9

A quantity is something that can be measured. What is the difference between a scalar and vector quantity?

Answer 9

Scalars only have a size. Vectors have a size and a direction.

Question 10

What kind of quantity is a force?

Answer 10

A vector quantity - because it has a direction (shown by the arrow)

Question 11

Which of the following are scalar quantities?
Temperature, mass, weight, speed, thrust, energy, volume

Answer 11

Temperature, mass, speed, energy, volume.
Thrust and weight are forces

Question 12

What is the resultant force of the two forces below

Answer 12

5N to the right

Question 13

A force of 5 N acts to the right, and a force of 3 N act to the left. Calculate the resultant force.

Answer 13

2N to the right

Question 14

Weight is the force acting on an object due to gravity. For any object on earth which direction does weight point?

Answer 14

Down (towards the centre of the earth)

Question 15

If the resultant force acting on an object is = 0, the object will remain stationary (not moving) or ____________

Answer 15

Will continue moving at a constant velocity (speed)

Question 16

If the resultant force acting on an object is not = 0, the object will either change ______ or change _______.

Answer 16

speed. direction.

Question 17

What word describes an object speeding up (increasing its speed)

Answer 17

acceleration

Question 18

What word describes an object braking (decreasing its speed)

Answer 18

deceleration

Question 19

What is the resultant force from combining the horizontal and vertical forces? (the purple arrow)

Answer 19

Using Pythagoras
sqrt( (5x5) + (3.5x3.5) ) = 6.1 N

Question 20

What is the scale of this diagram (how many N per cm)? What is the resultant force?

Answer 20

2N for every 1cm.
sqrt( (12x12) + (10x10) ) = 15.62 N

Question 21

What piece of equipment can you use to measure force?

Answer 21

A Newton-meter or force-meter

Question 22

What are two factors that increase air resistance?

Answer 22

The surface area of the object (think of a parachute) and the objects speed.

Question 23

An apple is sitting stationary on the teachers desk. Weight is one force acting on the apple, what is another?

Answer 23

The normal contact force (acting from the table upwards)