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Find an expression for the escape velocity of a test object.

Escape velocity is the velocity required to just escape the gravitational pull of a body. The gravitational force of a body is given by Newtons Law: F = GMm / r 2 (where G is the gravitational constant, M is...
CN
Answered by Ciara N. • Physics tutor
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Draw the electric field lines produced by a negative point charge and calculate the electric field strength at a distance of 50mm from a point charge of size -30nC.

The diagram should show a negative point charge with the electric field lines pointing towards the point charge. The separation of the lines should decrease as you get closer to the point charge. The lines s...
JB
Answered by Jemima B. • Physics tutor
3517 Views

Using Newton's law of universal gravitation, show that T^2 is proportional to r^3 (where T is the orbital period of a planet around a star, and r is the distance between them).

(Lets consider a simple planetary system composed of a planet orbiting a star. the gravitational force between the two is given by F=(GMm)/(r 2 ). Assuming the planet also moves in a circular orbit, we can c...
KS
Answered by Karanvir S. • Physics tutor
30846 Views

What is the difference between a longitudinal and a transverse wave?

Waves that go up and down in a curvy shape like you would draw on a piece of paper are called transverse waves. Scientifically, these are when the particles move in a direction that is perpendicular (90) fro...
SF
Answered by Sarah F. • Physics tutor
11698 Views

What is the stress in a cylindrical rod of 10.0cm diameter when loaded by 50.0N force at each end?

Stress = Force/Area and cross sectional area of a cyclinder = pi.r 2 As diameter = 10.0cm=0.1m r=0.05m so area = 3.14*0.05 2 = 0.00785m 2 As the force is 50.0N the stress is 50/0.00785=6369Nm -2 or 6.37kPa t...
RH
Answered by Rowan H. • Physics tutor
3933 Views