Further Mechanics

Question 1

What is meant by a forced vibration?

Answer 1

Oscillations where a periodic external driving force is applied

Question 2

Give an example of light damping

Answer 2

A pendulum or mass-spring system oscillating in air ( thick oil )

Question 3

State the 2 conditions for an object to be in simple harmonic motion

Answer 3

The magnitude of the acceleration is proportional to the displacement from the equilibrium position

And

The direction of the acceleration is opposite to that of the displacement

Question 4

Define the radian

Answer 4

The angle subtended by a circular arc with a length equal to the radius of the circle

Question 5

What is meant by critical damping?

Answer 5

Where an external force causes the system to become stationary at its equilibrium position in the shortest possible time

Question 6

At what point in an oscillation is the velocity 0?

Answer 6

At the maximum displacement

Question 7

On what factors does the time period of a simple pendulum depend on?

Answer 7

Length of string
Gravitational field strength

Question 8

What is the direction of the velocity of an object moving with circular motion?

Answer 8

At a tangent to the circle

Question 9

What provides the centripetal force for a vehicle going round a bend?

Answer 9

Friction between tires and road

Question 10

What is the relationship between the linear speed and the angular speed of an object traveling with circular motion?

Answer 10

V=wr

Question 11

What are the conditions for an object to be in uniform circular motion?

Answer 11

Moving in a circle at constant speed

Question 12

For a plane performing loops, at which stage of the loop is the normal contact force between the pilot and their seat the least?

Answer 12

At the top of the loop

Question 13

If a system is undergoing forced vibration, at what frequency does it oscillate?

Answer 13

The driving frequency ( frequency of the driving force )

Question 14

At what point in an oscillation is the acceleration maximum?

Answer 14

At the maximum displacement

Question 15

What is meant by light damping?

Answer 15

where an external force causes the amplitude of oscillations to decrease gradually over many oscillations

Question 16

What provides the centripetal force for a pilot in a plane performing vertical loops?

Answer 16

The resultant of the weight and the normal contact force between the pilot and the seat

Question 17

At what point in an oscillation is the kinetic energy a maximum?

Answer 17

At the equilibrium position

Question 18

How is displacement defined for an object moving in simple harmonic motion?

Answer 18

The distance and direction of an object from the equilibrium position

Question 19

What provides the centripetal force for a satellite orbiting a planet?

Answer 19

Gravitational force

Question 20

What is meant by a free vibration?

Answer 20

Oscillations that occur with no transfer of energy to or from the surroundings

Question 21

At what point in an oscillation is the acceleration zero?

Answer 21

At the equilibrium position

Question 22

On what factors does the time period of a mass-spring system depend?

Answer 22

Mass and the spring constant

Question 23

What is meant by the centripetal force?

Answer 23

The resultant force acting on an object that keeps it in circular motion

Question 24

At what point in an oscillation is the potential energy maximum?

Answer 24

At the maximum displacement

Question 25

In which direction does the centripetal acceleration act?

Answer 25

Towards the centre

Question 26

What is the definition of time period when considering circular motion?

Answer 26

The time taken for the object to complete one full rotation

Question 27

At what point in an oscillation is the velocity maximum?

Answer 27

At the equilibrium position

Question 28

At what point in an oscillation is the kinetic energy 0?

Answer 28

At the maximum displacement

Question 29

What is meant by heavy damping?

Answer 29

Where an external force is so strong that the oscillating system returns to the equilibrium position much more slowly than with critical damping

Question 30

For a plane performing loops, at which stage of the loop is the normal contact force between the pilot and their seat the greatest?

Answer 30

At the bottom of the loop

Question 31

What is meant by resonance?

Answer 31

Process by which the amplitude of oscillations of a system increases to a maximum

Question 32

What is the natural frequency of an object?

Answer 32

The frequency at which an object will oscillate when left to do so freely, with no driving or damping forces acting on it

Question 33

What is the maximum angle a simple pendulum can make with the vertical for its motion to be approximated to simple harmonic motion?

Answer 33

10 degrees

Question 34

When does resonance occur?

Answer 34

When the frequency of the driving force is equal to the natural frequency of the system

Question 35

What effect does damping have on resonance?

Answer 35

The greater the damping, the smaller the increase in amplitude of the oscillations and the further the resonant frequency is from the natural frequency

Question 36

What provides the centripetal force for a weight being swung in horizontal circles on the end of a string?

Answer 36

The tension in the string

Question 37

What is meant by damping?

Answer 37

The process by which an oscillating object loses energy to its surroundings caused by damping forces

Question 38

Why is an object in circular motion accelerating, even though its liner speed is constant?

Answer 38

It is constantly changing direction so changing velocity. Acceleration is the rate of change of velocity.