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Explain in terms of the motion of the molecules of the gas why the volume of gas must increase if the pressure is to remain constant as the gas is heated.

- When gas is heated, the molecules gain kinetic energy. This causes more collisions of greater force per unit time with the wall of the container. If the pressure is constant, then fewer collisions per unit...
CS
Answered by Connor S. • Physics tutor
10125 Views

A spherical object of mass 150kg is orbiting the Earth. The distance between the centre of the object and the centre of the Earth is 25,000m. What is the kinetic energy of the object?

This is an example of circular motion caused by a centripetal force. In this case, the centripetal force is the gravitational force between the Earth and the object. Linking the equations for circular motion...
RL
Answered by Ryan L. • Physics tutor
3347 Views

Explain how fluorescent tubes work

Fluorescent tubes are filled with low pressure mercury, when an electric current is passed through, the electrons in mercury are excited and move to a high energy level, this high level state is unstable and...
MW
Answered by Michael W. • Physics tutor
34526 Views

A ball of mass 0.7 kg strikes the wall at an angle of 90 degrees with speed 72 km/h. Consider that the bounce lasts for 0.1 s and is perfectly elastic. What is the magnitude of the average reaction force from the wall that acts on the ball?

initial speed: v = 72 km/h = 20 m/s. mass: m = 0.7 kg time of the impact: t = 0.1 s average force: F The speed after impact is the same as initial speed, but velocity has got the opposite direction. Therefor...
FM
Answered by Filip M. • Physics tutor
4510 Views

Resolving the forces for an object suspended on two strings.

Imagine a following situation: a stationary (not moving) object with a mass of 5 kg is suspended in the air by two strings. The angles between strings and the vertical directions are 15 and 55 degrees. What ...
FW
Answered by Filip W. • Physics tutor
19806 Views