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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 you a ...
NC
Answered by Namir C. • Maths tutor
6094 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 so ...
DH
Answered by Dylan H. • Physics tutor
4471 Views

A kettle is found to output 65J when its input energy is 100J. What is the efficiency of the kettle, and what happens to the rest of the energy?

Efficiency=useful energy /input energy x 100, so for the kettle, efficiency = 65/100 x 100 = 65% efficient. The rest of the energy is wasted as heat energy in the kettle/sound energy.
JL
Answered by Joshua L. • Physics tutor
23023 Views

How does HIV invade cells?

The way a simple virus invades a cell is with double stranded DNA replication. The virus has a coat of protein covering the DNA, once bound to the side of the cell the virus releases the DNA where it is then...
SC
Answered by Susanna C. • Biology tutor
4259 Views

How should I structure my essay?

The way in which an essay is structured makes a huge difference to its effectivity and is one of the key criteria in receiving a good mark. The first crucial component of a successful essay is a good introdu...
JB
Answered by Jasmine B. • English tutor
3047 Views