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A geostationary satellite is orbiting Earth, a) What is meant by a geostationary orbit? b) Calculate the height at which the satellite orbits above the surface of the Earth. The radius of the Earth is 6400km and its mass is 6x10^24 kg.

a) A geostationary orbit is when the satellite remains vertically above the same point on the equator at all all times and consequently has an orbital period of 24 hours. b) Use the equation T^2=4(PI)^2(r...

Answered by Edward N. • Physics tutor

19739 Views

A triangle has sides A, B and C. The side BC has length 20cm, the angle ABC is 50 deg and angle BAC is 68 deg. a) Show that the length of AC is 16.5cm, correct to three significant figures. b) The midpoint of BC is M, hence find the length of AM

a) The answer to this question is quite simple, it is all dependent on the pupil realising that they need to use the sine rule. This rule for this triangle is: BC/sin(BAC) = AC/sin(ABC) Once they get this...

Answered by Ravi S. • Maths tutor

4886 Views

What is meant by the "fluid-mosaic" model of cell membrane structure?

The cell membrane consists of a double layer of phospholipids, with proteins floating in it. Phospholipids are a type of molecule with a phosphate head, and fatty tails, which form a double layer around t...

Answered by Harriet H. • Biology tutor

25434 Views

How do I find the inverse of a 2x2 matrix?

Hiya! So the very first thing we need to do is find the determinant, which is just a fancy word to describe a matrix; for a 2x2 matrix, it's equal to "ad-bc", where: (a b c d) This will give...

Answered by Namir C. • Maths tutor

5015 Views

A DVD is dropped from rest. The DVD does not reach terminal velocity before it hits the ground. Explain how the acceleration of the DVD varies from the instant it is dropped until just before it hits the ground.

In the instant when the DVD is dropped, it will have an acceleration of g, with no drag force acting on it as it is not moving. As the DVD accelerates downwards, the drag force acting on it increases and ...

Answered by Dylan H. • Physics tutor

3766 Views