PAG 10.1 Investigating Factors Affecting SHM

Question 1

State the defining equation of SHM

Answer 1

a = -w2x

Question 2

What is simple harmonic motion?

Answer 2

Motion where the object’s acceleration is proportional to the displacement and in the opposite direction to the displacement

Question 3

What is the relationship between pendulum’s time period and its mass?

Answer 3

Time period of a pendulum does not depend on its mass

Question 4

State the equation used to calculate time period of a pendulum

Answer 4

T = 2π √L/g

Question 5

What two conditions must be met when carrying out this experiment using a pendulum?

Answer 5

1) Amplitude should be small
2) pendulum should oscillate in a straight line

Question 6

Why must oscillations only be small when carrying out this experiment?

Answer 6

To use small angle approximations and apply for small displacements

Question 7

How should you measure the time period of an oscillating simple pendulum

Answer 7

Measure time taken for 10 oscillations and repeat 3 times and find average time
Then divide by 10 to get average time period of 1 oscillation

Question 8

What could be added to your apparatus to help measure the time period accurately?

Answer 8

A fiducial marker could be added at the centre of the oscillation to show exactly when an oscillation has been completed

Question 9

When plotting a graph of T squared against L, what does the straight line through the origin demonstrate?

Answer 9

Directly proportional relationship

Question 10

How could the gravitational field strength be estimated from T squared against L

Answer 10

‘g’ is given by 4πr^2/gradient

Question 11

State the equation used to calculate the time period of a simple mass-spring oscillator

Answer 11

T = 2π√(m/k)

Question 12

Describe how the time period of a simple mass-spring oscillator varies with the length of the spring

Answer 12

Time period is independent on the length of the string.
It depends on the mass and spring constant

Question 13

When hanging a mass-spring system from a clamp stand, what safety precautions should be taken?

Answer 13

Counterweight or G clamp should be attached to the base of the clamp stand to provide a counter moment to prevent it toppling

Question 14

What safety precautions should be taken when adding masses to a spring?

Answer 14

Safety goggles in case the spring snaps.
Ensure you never stand with your feet directly below the masses in case they fall

Question 15

How could the spring constant be calculated from a graph of T squared against m for a simple mass-spring oscillator?

Answer 15

‘k’ is given by 4πr^2/gradient

Question 16

If the length of a pendulum is quadrupled, how will its time period change?

Answer 16

Time period is directly proportional to the square root of its length

Question 17

How will the mass of a mass-spring oscillator need to be changed to halve its time period

Answer 17

Time period is directly proportional to the square root of its mass

Question 18

How will the time period of a mass-spring oscillator change if the spring is replaced with one of quarter its stiffness?

Answer 18

Time period is inversely proportional to the square of the spring constant