End Of Unit Questions Flashcards
Why is it easier to move a big rock with a crow bar than your hands?
A crowbar allows you to apply the same force at a greater distance from the pivot so the moment is greater
Why must an object moving in a circle be accelerating?
Because it is changing velocities as it changes directions constantly so it must be accelerating
A force of 15N is applied at right angles to a spanner of 0.5 m long. What is the moment of this force?
7.5Nm
An object that is freely suspended is displaced slightly then let go. Where will it’s centre of mass be when it comes to rest?
Directly below the point of suspension
What is the pressure exerted on the ground by a block of weight 20N if the area in contact with the ground is 0.008m2?
2500Pa
What is a centripetal acceleration?
An acceleration towards the centre of a circle
Why will an oscillating simple pendulum eventually come to rest?
It transfers energy doing work against friction at the pivot and air resistance
What is the frequency of a pendulum with a time period of 0.02s?
50Hz
What is the amplitude of oscillation of a simple pendulum?
The distance from the highest point on one side to the highest point on the other side
When will an object topple?
When the line of action of its weight is outside its base
What is the moment of a force?
The turning effect of a force
