Acceleration

Question 1

What is equation one for acceleration?

Answer 1

Change in velocity/ time

Question 2

How do you calculate the change in velocity?

Answer 2

Final velocity - Initial velocity

Question 3

What are the units for acceleration?

Answer 3

m/s²

Question 4

How do you a veloctiy-time graph to measure acceleration?

Answer 4

You work out the gradient of the graph

(using a tangent to work out the gradient if it’s a curve)

Question 5

How do you work out the distance travelled using a velocity-time graph?

Answer 5

You work out the area of space below the velocity-time graph

(multiplying the velocity and time)

Question 6

What does a constant velocity look like on a velocity-time graph?

Answer 6

A straight horizontal line

Question 7

What is deceleration?

Answer 7

Slowing down (negative acceleration)

so when you calculate a value and they say give thedeceleration you can drop the negative sign as it is already negative

Question 8

How do you work out the area beneath a velocity-time graph and thus the distance using the counting squares method?

Answer 8

You do:

area of each square x number of squares

if less than half of the square is under the graph, don’t count it. If more than half is under the square, count it

Question 9

What is the second equation for uniform acceleration?

Answer 9

V² - U² = 2as

V= final velocity
U= Initial velocity
a= acceleration
s= distance

Question 10

Explain how an object falls through a fluid

Answer 10

An object falling through a fluid will initially accelerate due to the downwards force of weight due to gravity being exrted on it

A it continues to fall ad its veloccity increase, the acceleration will decrease and the air resistance acting upwards on the object increases, and over time the resultant force acting on the object decreases and becomes zero

And now the object is moving at its terminal velocity

Question 11

Explain how a sky diver falls in the air when they open their parachute

Answer 11

• When they open their parachute the air resistance being exerted on the diver increases
• This increases the upwards resultant force acting on the diver and causes them to decelerate
• As the diver’s velocity decreases, the air resistance being exerted on the diver decreases and soon the air resistance will have the same magnitude as the weight the resultant force becomes zero
• Now the diver falls with a lower terminal velocity