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What does the velocity of an object tell you?
The velocity of an object tells you both the speed and direction it's travelling in.
1 of 20
What does the gradient of a distance-time graph represent?
The gradient of a distance-time graph represents the sped. The higher the speed, the steeper the slope is.
2 of 20
Give a definition of the term 'acceleration'.
The acceleration of an object is how quickly its velocity is changing. A change in velocity can be change in speed or change in direction or both.
3 of 20
If a car travelling at 5 m/s accelerates to 13 m/s in 4 seconds what is its acceleration?
(13 m/s - 5 m/s) divided by 4 seconds = 2 m/s^2
4 of 20
What does an upward sloping line on a velocity-time graph tell you?
An upward sloping line on a velocity-time graph tells you the object is accelerating.
5 of 20
What does a horizontal line on a velocity-time graph tell you?
A horizontal line on a velocity -time graph tells you that the object is moving at a steady speed.
6 of 20
Friction opposes the movement of a book across a table. A person pushes against the side of the book to make it slide along the table. describe the forces acting on the book at the point it starts to move.
If a person pushes against the side of a book to make it slide along a table the frictional force matches the applied force until the object begins to move. At this point the applied force has become greater than the frictional force.
7 of 20
If the resultant force acting on a moving object is zero what will happen to its motion?
If the resultant force acting on a moving object will continue to move at the same speed and the same direction.
8 of 20
If the resultant force acting on a moving object is not zero, what will happen to its motion?
If the resultant force acting on a moving object is not zero the object will accelerate in the direction of the resultant force.
9 of 20
Name the main force acting against the motion of a car.
Air resistance is the main force acting against the motion of a car.
10 of 20
When a car is moving at a steady speed how does air resistance compare with the driving force?
when a car is travelling at a steady speed the air resistance is equal to and opposite to the driving force.
11 of 20
Why are heavy objects much harder to slow down or change direction?
The greater the mass and velocity of an object the greater its momentum will be. Heavy objects are much harder to slow down or change direction because they have a lot of momentum.
12 of 20
what is the gravitational potential energy?
Gravitational potential energy is the energy that an object has due to its position in a gravitational field.
13 of 20
Why do objects have gravitational potential energy?
When an object is raised vertically work is done against the force of gravity and the object gains gravitational potential energy.
14 of 20
A window cleaner with with a mass of 70 kg climbs to a height of 5 m on his ladder. How much GPE does he gain?
GPE (J) = m (kg) x g (N/kg) x h (m) = 70 kg x 10 N/kg x 5 m = 3500 J
15 of 20
What does the kinetic energy of a moving object depend on?
The kinetic energy of an object depends on its mass and speed.
16 of 20
Why does increasing the speed of an object make a bigger difference to the amount of kinetic energy it has than increasing its mass.
Increasing the speed of an object makes a bigger difference to the amount of kinetic energy it has than increasing its mass because kinetic energy depends on the speed squared so if you double the speed, the kinetic energy increases by a factor of 4.
17 of 20
A car with a mass of 900 kg is travelling at 5 m/s. How much kinetic energy does it have?
KE (J) = 1/2 x m x v^2 = 1/2 x 900 kg x (5 m/s)^2 = 11250 J
18 of 20
The car on the previous flashcard speeds up to 15 m/s. How much kinetic energy does it now have?
1/2 x m x v^2 = 1/2 x 900 kg x (15 m/s)^2 = 101 250 J
19 of 20
A man pushes a wheelbarrow with a force of 80 N for a distance of 40 m. How much work does he do?
Work done = Force x Distance = 80 N x 40 m = 3200 J
20 of 20

Other cards in this set

Card 2

Front

What does the gradient of a distance-time graph represent?

Back

The gradient of a distance-time graph represents the sped. The higher the speed, the steeper the slope is.

Card 3

Front

Give a definition of the term 'acceleration'.

Back

Preview of the front of card 3

Card 4

Front

If a car travelling at 5 m/s accelerates to 13 m/s in 4 seconds what is its acceleration?

Back

Preview of the front of card 4

Card 5

Front

What does an upward sloping line on a velocity-time graph tell you?

Back

Preview of the front of card 5
View more cards

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