M - Statistics & Mechanics 1 - 9) Constant acceleration

Question 1

Meanings of the parts of displacement-time graphs

Answer 1

• Gradient → velocity
• Horizontal line → stationary
• Straight upwards- or downwards-sloping line → constant velocity
• Curve → acceleration or deceleration

Question 2

Formula for average velocity

Answer 2

Average velocity = displacement from starting point ÷ time taken

Question 3

Formula for average speed

Answer 3

Average speed = total distance travelled ÷ time taken

Question 4

Meanings of the parts of velocity-time graphs

Answer 4

• Gradient → acceleration
• Horizontal line on x-axis → stationary
• Horizontal line above x-axis → constant velocity
• Straight upwards- or downwards-sloping line → constant acceleration

Question 5

Way to find displacement from a velocity-time graph

Answer 5

Find area under the curve → velocity × time

Question 6

Formulas for each of the missing parts of SUVAT

Answer 6

• s → v = u + at
• u → s = vt - ½at²
• v → s = ut + ½at²
• a → s = (u + v)/2 × t
• t → v² = u² + 2as

Question 7

Method to find the required value of one of the SUVAT

Answer 7

1. Use the equation corresponding to the missing part of SUVAT
2. Insert numbers into equation
3. Rearrange to find required value

Question 8

How gravity works in terms of acceleration of an object

Answer 8

• Downwards towards Earth → acceleration is g = 9.8 m/s²
• Upwards away from Earth → acceleration is g = -9.8 m/s²