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There is a point between the Moon and the Earth where the gravitational attractions are equal and opposite. How much further is this point from the Earth than the Moon

Using the formula for gravitational attraction between the Moon/Earth and a test mass, m. We determine F_E = (G*M_Em)/(r_E² ), F_M= (GM_M<...

Answered by Paul D. • Physics tutor

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Sound waves are longitudinal. Describe a longitudinal sound wave?

A wave where the oscillations are parallel to the direction of energy transfer causing areas of compression and rarefaction

Answered by Marie B. • Physics tutor

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A rocket travels with constant velocity in a straight line in deep space. A ball is thrown from the back to the front (ie from the thrusters to the nose). Describe the path of the ball. Describe the path if the rocket were accelerating along this line.

Consider first what happens when the rocket travels with constant velocity. Constant velocity implies that there are balanced forces (or indeed no forces) acting on the rocket. This is Newtons 1st Law. We...

Answered by Sam W. • Physics tutor

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Derive an expression for the time taken, (t) for a test mass to fall to the ground from a height (h) in a uniform gravitational field (g = 9.81 ms^-2)

We first build an intuition for exactly what acceleration is and what we expect to happen. In the uniform gravitational field approximation, we assume h to be much less than the radius of the Earth. There...

Answered by Charlie B. • Physics tutor

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Explain how an electromagnetic motor works?

A moving current in a magnetic field produces a force according to Fleming's Left Hand Rule. When a loop of wire with a current moving through it cuts magnetic field lines, movement is induced along the w...

Answered by Hannah S. • Physics tutor

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