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How do stars form?

A star is formed from a nebulae, which is a cloud of dust and gas. The dust and gas particles are drawn together by the gravitational attraction between them. As the nebulae contracts, the dust and gas pa...

Answered by Stephen S. • Physics tutor

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A runner of weight 588N runs at a speed of 8 miles/hr. What is the kinetic energy of the runner? Determine the power exerted by the runner over a distance of 10m.

KE = 1/2mv^2m = 588/9.8 = 60 kgv = 8 miles/hr = 3.56 m/sKE = 379 JP = E/tt = d/v = 10m/3.56m/s = 2.81 sP = 135 W

Answered by Eliza D. • Physics tutor

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In the Rutherford alpha scattering experiment, most particles passed straight through the foil with little or no deflection. What can be deduced about the structure of the atom from this?

Answer: Most of the atom's mass must be concentrated in a small area at the centre of the atom. This is known as the nucleus.

Answered by Megan R. • Physics tutor

1884 Views

Explain the difference between energy and power.

Power is the rate at which energy is transferred. For example, a typical kettle may use 1.2 kiloWatts (kW) for about 2 minutes to boil water. This means that the kettle uses 1200 Joules of energy per seco...

Answered by Henry J. • Physics tutor

2809 Views