(Done) Forces (Paper 2)

Question 1

Define vector quantity

Answer 1

• A quantity that has both direction and magnitude

Question 2

Give 5 examples of vector quantities

Answer 2

• Force
• Velocity
• Displacement
• Acceleration
• Momentum

Question 3

Define scalar quantity

Answer 3

• A quantity that only has magnitude and no direction

Question 4

Give 5 examples of scalar quantities

Answer 4

• Speed
• Distance
• Mass
• Temperature
• Time

Question 5

How are vectors traditionally represented

Answer 5

• As an arrow, with size of the arrow showing magnitude

Question 6

What are the two types of force

Answer 6

• Contact
• Non contact

Question 7

Define contact force

Answer 7

• When two objects have to be touching for a force to act

Question 8

Define non contact force

Answer 8

• When two object do not need to be touching for a force to act

Question 9

Give 4 examples of contact forces

Answer 9

• Friction
• Air resistance
• Tension in ropes
• Normal contact force

Question 10

Give 3 examples of non contact forces

Answer 10

• Magnetic force
• Gravitational force
• Electrostatic force

Question 11

Define gravitational force

Answer 11

• Force of attraction between masses

Question 12

Define weight

Answer 12

• The force acting on an object due to gravity

Question 13

What causes weight

Answer 13

• The gravitational field

Question 14

What factors affect gravitational field strength

Answer 14

• Proximity to mass causing the field
• Size of the mass causing the gravitational field

Question 15

Define elastic deformation

Answer 15

• When an object returns to its original shape and size once the force is removed

Question 16

Define inelastic deformation

Answer 16

• When an object is unable to return to its original size and shape after the force is
  removed

Question 17

Define limit of proportionality

Answer 17

• Where the extension of an elastic object is no longer proportional to the force applied on the object

Question 18

Effect of gears on the moment

Answer 18

• The teeth on gears interlock, causing the other gears to turn, in the opposite direction
• Gears are used to transfer rotational force from one place to another
• The moment being transferred from a smaller gear to a bigger gear will increase as the distance from the pivot is greater

Question 19

State Newton’s first law

Answer 19

• A force is needed to change motion

Question 20

Why do objects reach terminal velocity whilst falling through a fluid

Answer 20

• The frictional forces of the fluid against the object eventually reach equilibrium with the accelerating forces

Question 21

State Newton’s second law

Answer 21

• Acceleration is proportional to resultant force

Question 22

Define inertia

Answer 22

• The tendency for motion to remain unchanged

Question 23

Define inertial mass

Answer 23

• A measurement of how difficult it is to change the velocity of an object

Question 24

Describe Newton’s third law

Answer 24

• When two objects interact, the forces they exert on each other are equal and opposite

Question 25

Name the force often used when describing the "equal and opposite" force in Newton's third law

Answer 25

- Normal contact force

Question 26

State the equation for stopping distance

Answer 26

- Stopping distance = Thinking distance + braking distance

Question 27

List the factors that affect thinking distance

Answer 27

- Speed - Reaction time

Question 28

List the factors that affect braking distance

Answer 28

- Speed - Weather or road conditions - Quality of brakes - Quality of tires

Question 29

State the conservation of momentum

Answer 29

- Within a closed system, momentum before impact is always equivalent to momentum after impact