What is required for an object to travel in a circular motion?
Centripetal force
100
Define a moment
A moment is the turning effect of a force about a fixed point.
100
Give two examples of non-renewable energy resources.
Coal
Oil
Natural Gas
Nuclear
200
Will I weigh more on the moon or on the earth, or will I weigh the same on both?
Earth - gravity is stronger
200
What are the units for density?
kg/m(3)
200
In what direction does a centripetal force act whenever it is at the bottom the circle?
Towards the centre of the circle
200
Give four examples of when moments are useful.
Crow bars
Wheelbarrows
Fishing Rods
Door Handle
See-saws
Pulleys
200
Give two examples of renewable energy.
Wind
Solar
Hydroeletric etc.
300
If my mass on the moon is 350kg, and my mass on Jupiter is 350kg, what does this tell us about the value of gravity on Jupiter and the moon?
Nothing!
300
a) If gold has a mass of 30kg at a volume of 7.5m(3), what is the density of gold?
b) What will the density of gold be for a block of volume 15m(3)
a) 4 kgm(-3)
b) 4 kgm(-3)
300
If the mass of the object in a circular motion increases, what happens to the centripetal force?
It increases
300
What is the principle of moments?
When an object is in equilibrium the sum of the clockwise moments is equal to the sum of the anticlockwise moments.
300
State the conservation of energy law.
Energy can not be created or destroyed, it can only be transferrred.
400
A car has a weight of 250N on the earth. What is the mass and weight of the same car on Jupiter, where gravity is 20% of the value of gravity on earth?
Mass = 25kg
Weight = 50N
400
Describe an experiment to measure the density of regular and irregular objects - including equipment used.
...
400
What happens to the centripetal force as the radius of the circle increases?
It decreases
400
If a metre rule is pivoted at the centre, and a mass of 10kg is hanging from one side at the 20cm mark on the metre rule, at what position is a mass of 20kg hanging if the metre rule is balanced?
65cm
400
Draw an energy transfer diagram for a torch.
Electrical - light + heat
500
If my mass on the moon is 75kg, where gravity is valued at 1.66. What is my weight on the earth and the moon?
Earth - 750N
Moon - 124.5N
500
A cylinder of stainless steel, length 2.5m has a mass of 12kg. The face of the cylinder has a diameter of 20cm. What is the density of the cylinder?
A = pi x r(2) = 0.1256
Volume = area x length = 0.314
density = mass / volume = 38.2 kgm(-3)
500
If the centripetal force is removed, in what direction will the object move?
At a tangent to the circle
500
A uniform metre rule is pivoted at the 30cm mark. There is a weight of 10N hanging from the 0cm mark on the ruler. If the ruler is balanced, what is the weight of the ruler?
15N
500
State 9 different types of energy.
Chemical
Gravitational Potential
Kinetic
Nuclear
Light
Heat
Sound
Electrical
Magnetic