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Steel has a density of 8030kg/m^3. Show that a steel ball with a diameter of 5cm weighs approximately 5N

Using Weight = mass*gravitational strength

Using: Mass = density * volume

Using Volume = (4/3)pir³

Radius = 2.5cm = 0.025m

Volume = (4/3)pi0.025

Answered by Sameh H. • Physics tutor

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What is the total energy of a spaceship of mass m, orbiting a planet of mass M in a circular orbit with radius r? The ship and the planet are taken to be an isolated system.

In the non-inertial frame of reference of the spaceship, a centrifugal and a gravitational force acts on the spaceship. If its mass is m and the positive direction is radially outwards, we have:

F...

Answered by Ivan D. • Physics tutor

2574 Views

Why do skydivers have a terminal velocity?

People and things keep doing the same thing until a force makes them change according to Newton.

When a skydiver jumps out of a plane they have zero velocity downwards but the force of gravity is p...

Answered by Peter F. • Physics tutor

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A pan is on the stove ready to boil some peas. The water inside it is heated by convection, and as you watch you can see a convection current occur. Explain what convection is and why convection currents happen.

Part A) Convection occurs in liquids. In this process, more energetic particles move from warmer regions to cooler ones and take their energy with them.

A convection current happens because when a ...

Answered by Kiaya P. • Physics tutor

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Describe the process of nuclear fission is induced

Single and slow moving neutron strikes a uranium nucleus. This results in the nucleus to be large and unstable. The unstable nucleus splits into two unequal nuclei and some fast neutrons. The neutrons can...

Answered by Sudip S. • Physics tutor

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