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Explain why the velocity of a car moving at a constant speed around a bend changes.

Velocity is a vector quantity, that is, it is fully described by magnitude and direction. Even though the car moves at a constant speed, its direction varies as it moves around the bend. Since there is a cha...
NA
Answered by Nicholas A. • Physics tutor
12565 Views

State the life cycle of a star about the same size of our sun

Nebula (cloud of gas and dust)ProtostarMain sequence starRed giantWhite dwarfBlack dwarf (some students may not need to know this depending on their GCSE exam board and specification)
GC
Answered by Grace C. • Physics tutor
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Describe a simple experiment to determine the speed of sound in air.

One method to measure the speed of sound would require two people, a large open space, a starting pistol that produces smoke instantaneously when fired, a stopwatch and a tool to measure long distances (e.g....
AE
Answered by Alex E. • Physics tutor
45615 Views

Explain the difference between speed and velocity.

Speed is the rate of change in direction, whereas velocity is the rate of change in displacement. This means that an object's velocity has an associated direction whereas its speed doesn't.If a car travells ...
MC
Answered by Mark C. • Physics tutor
3814 Views

According to Newton's third law, every action has an equal and opposite reaction. Why then does a box move when I push it? Shouldn't the two opposing forces cancel out to a zero net force?

The key to this question is realising that the action and corresponding reaction refer to forces that act on different objects . When I push the box, I exert a force on the box. As a result of this force, th...
ES
Answered by Ellen S. • Physics tutor
6831 Views