Accelerated Motion

Question 1

What is the equation for acceleration?

Answer 1

=change in velocity divided by time taken

Question 2

Give all the constant acceleration equations

Answer 2

v=u+at

v²=u²+2as

s=½(u+v)t

s=ut+½at²

Bonus: s=vt-½at²

Question 3

Define acceleration

Answer 3

The rate of change of velocity

Question 4

What can be deduced from the gradient of this graph?

Answer 4

Positive gradient shows constant acceleration

Question 5

What can be deduced from the gradient of this graph?

Answer 5

The greater the slope, the greater the acceleration

Question 6

What can be deduced from the gradient of this graph?

Answer 6

A negative slope shows deceleration (a is negative)

Question 7

What can be deduced from the gradient of this graph?

Answer 7

The gradient is changing, so the acceleration is changing.

The acceleration is getting smaller

Question 8

What can be deduced from the gradient of this graph?

Answer 8

Acceleration = 0

The veocity is constant

Question 9

How is acceleration shown on a velocity time graph?

Answer 9

The gradient equals acceleration

Question 10

What does the area under a velocity time graph show?

Answer 10

Displacement

Question 11

Descibe an experiment using one light gate to find acceleration

Answer 11

• one light gate
• trolley with two cards
• timer

The timer measures how long the first card breaks the light beam for. It will work out the intial speed u. The time is measured for the sectond card, then it will work out the final speed v. The time is measured between cards. It will calculate a by using

u=l₁ /t₂-t₃

v=l₂/t₄-t₃

a=(v-u)/t₃-t₁

Question 12

Describe an experiment using a ticker-timer to find acceleration

Answer 12

• ticker-timer
• trolley

Ticker marks every 1/50s. Every five dots represents 0.1s is a section. The length of each section gives the displacement in 0.1s, which can be used to find the average velocity. This is repeated for each section of the tape. Draw a velocity time graph.

Question 13

Describe an experiment using a motion sensor to find acceleration

Answer 13

• motion sensor
• trolley

Finds velocity. Calculates acceleration from values of velocity. Not precise.

Question 14

Describe an experiment using an accelorometer to find acceleration

Answer 14

• acclerometer card
• trolley

When the trolley accelerates forwards, the pendulum swings backwards. When the pendulum is at midpoint, the trolley is at a constant speed (or stationary). (the greater the angle, the greater the acceleration)