Forces
A push or pull acting on an object.
What is a force?
The unit of momentum.
What is kg.m/s?
The stored energy in an object due to its height above the Earth's surface.
What is gravitational potential energy?
The poles of two magnets that repel each other.
What are like poles?
The splitting of a large atomic nucleus.
What is nuclear fission?
The force that acts on an object moving through a fluid, increasing with speed.
What is drag (air resistance)?
The change in momentum of an object is also known as this quantity.
What is impulse?
A resource that will not run out on a human timescale.
What is a renewable energy resource?
The direction of force on a current-carrying conductor can be found using this rule.
What is Fleming's Left-Hand Rule?
The particles released in fission that can trigger futher reactions.
What are neutrons?
The relationship between force, mass and acceleration. F = ma.
What is Newton's Second Law?
A 3 kg object moving at 4 m/s comes to rest. Calculate its initial momentum.
What is 12 kg.m/s?
A device transfers 500 J of energy with 250 J useful output. Calculate efficiency.
What is 50% (or 0.5)?
The effect produced when a current flows through a conductor in a magnetic field.
What is the motor effect?
The fuel commonly used in nuclear fission reactors.
What is uranium (uranium - 235)?
Explain why terminal velocity occurs for a falling object.
What is drag increases until it equals weight, resulting in zero resultant force?
What is clockwise moments equal anticlockwise moments?
The energy transferred when a force moves an object through a distance.
What is work done?
Explain why transformers only work with alternating current (AC).
What is AC produces a changing magnetic field needed to induce voltage?
Explain why moderators are used in nuclear reactors.
What is to slow down neutrons to increase the chance of further fission?
A car increases its speed from 10 m/s to 20 m/s in 5 seconds. Calculate its acceleration.
What is 2 m/s2?
A 0.5 kg ball moving at 6 m/s rebounds at 4 m/s in the opposite direction. State the change in momentum.
What is 5 kgm/s (in opposite direction)?
A device transfers 600 J of energy in 3 seconds. Calculate its power.
What is 200 W?
State how the direction of the magnetic field around a current-carrying wire can be determined.
What is the right-hand grip rule?
A radioactive sample has a half-life of 6 hours. What fraction remains after 18 hours?
What is 1/8?