# P4 - Physics GCSE

0.0 / 5

HideShow resource information

- Created by: hamzayasin
- Created on: 03-10-14 16:50

What is velocity?

A measurement of an object's speed and direction of travel.

1 of 40

What is the formula for speed?

Speed (m/s) = Distance travelled (m) / Time taken (s). This calculates average speed.

2 of 40

What is instantaneous speed?

The speed of an object at a particular point in time.

3 of 40

What is a distance-time graph?

A plot of distance against time, the gradient of which is a measure of the object's speed- the steeper the slope, the greater the speed.

4 of 40

What is displacement?

A measurement of distance from a fixed point or origin. It can take a positive or negative value, depending on the direction from the origin.

5 of 40

What is a displacement-time graph?

A plot of displacement against time, the gradient of which gives the object's velocity, so it can have a positive or negative gradient.

6 of 40

What is instantaneous velocity?

The speed and direction of an object at any given time.

7 of 40

What does a curved distance-time graph show?

The speed of the object is changing as it travels. Plotting a straight line from beginning to end can give the average speed, but it is difficult to calculate instantaneous speed from it.

8 of 40

What is a speed-time graph?

A plot of speed against time, the gradient of which gives the object's acceleration. The steeper the slope, the faster the rate of acceleration.

9 of 40

What is a velocity-time graph?

A plot of velocity against time, the gradient of which gives the object's acceleration. Because velocity is involved, one axis can have negative values.

10 of 40

What is the formula for acceleration?

Acceleration (m/s (squared)) = Change in speed (m/s) / Time taken (s).

11 of 40

What is an interaction pair?

Two equal and opposite forces that occur when two objects interact with each other and one exerts a force on the other.

12 of 40

What is gravity?

The force of attraction between two masses, e.g. people to the Earth.

13 of 40

What is air resistance?

The force of the air pushing against an object, slowing it down.

14 of 40

What happens in rocket and jet engines?

The engine pushes has backwards (action) and the gas pushes the rocket forward (reaction).

15 of 40

What is the reaction of the surface?

A force that occurs as a result of an object resting on a surface, being pulled down by gravity. The force is of the surface pushing up on the object.

16 of 40

What is friction?

The force that occurs when two objects slide past each other, in order to stop the objects moving.

17 of 40

How are forces shown on a diagram?

Arrows represent forces: the size of the arrow shows the size of the force, and the direction of the arrow shows the direction the force is moving in.

18 of 40

What is a resultant force?

The overall effect of adding or subtracting the forces working on an object (forces in the same direction are added, those in an opposite direction are taken away).

19 of 40

What is momentum?

The measure of the motion of an object.

20 of 40

What is the formula for momentum?

Momentum (kg m/s) = Mass (kg) X Velocity (m/s).

21 of 40

What happens when the resultant force acting on an object is zero?

The object's momentum will not change (if it is stationary, it will remain stationary; if it is already moving, it will continue moving at a steady speed in the same direction).

22 of 40

What happens if the resultant force acting on an object is not zero?

A change in momentum occurs- the object could speed up, slow down, start moving, or change direction.

23 of 40

What is the formula for change in momentum?

Change in momentum (kg m/s) = Resultant force (newtons, N) X Time the force acts for (s).

24 of 40

What is a collision?

Where two objects come together, causing changes in the momentum. In a car crash, the sudden changes in momentum can affect the car and the passengers, leading to damages and injuries.

25 of 40

What are road safety devices?

Seat belts, air bags, crumple zones (at the front, which crumple on impact) etc. which reduce the impact of the collision on the passengers.

26 of 40

What is a vehicle's driving force?

The forward force created by the engine or other energy source (cyclists etc.).

27 of 40

What is a counter force?

The force on an object, caused by friction and air resistance.

28 of 40

Why does a vehicle speed up?

The driving force is bigger than the counter force.

29 of 40

Why does a vehicle travel at a constant speed?

If the driving force is equal to the counter force.

30 of 40

Why does a vehicle slow down?

The driving force is smaller than the counter force.

31 of 40

What is kinetic energy?

The energy of a moving object, dependent on its mass and velocity.

32 of 40

What is the formula for kinetic energy?

Kinetic energy = 1⁄2 × mass × speed(squared)

33 of 40

What forces act on an object thrown upwards?

Air resistance and gravity- they slow down the object, which is moving as a result of the initial force upwards.

34 of 40

What forces act on a falling object?

Gravity- pulls the object downwards, causing it to accelerate and the air resistance force to increase. When air resistance and gravity are equal, the object moves at a constant speed.

35 of 40

What is work done?

A transfer of energy, as a result of a force acting on an object. If the work is done on an object, it gains energy; if the work is done by an object, it loses energy. The total amount of energy remains the same (it is conserved).

36 of 40

What happens when a force makes an object's velocity increase?

Work is done on the object by the force, and the object gains kinetic energy.

37 of 40

What is the formula for work done?

Work done (J) = Force (N) X Distance moved in the force's direction (m).

38 of 40

What is GPE?

Gravitational Potential Energy- the energy created by the work done on an object being lifted. It has the potential to do work.

39 of 40

What is the formula for GPE?

Change in GPE (J) = Weight (N) X Vertical height difference (m).

40 of 40

## Other cards in this set

### Card 2

#### Front

What is the formula for speed?

#### Back

Speed (m/s) = Distance travelled (m) / Time taken (s). This calculates average speed.

### Card 3

#### Front

What is instantaneous speed?

#### Back

### Card 4

#### Front

What is a distance-time graph?

#### Back

### Card 5

#### Front

What is displacement?

#### Back

## Similar Physics resources:

2.5 / 5

0.0 / 5

2.0 / 5

0.0 / 5

0.0 / 5

0.0 / 5

0.0 / 5

4.0 / 5

## Comments

No comments have yet been made