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Two masses A and B, 2kg and 4kg respectively, are connected by a light inextensible string and passed over a smooth pulley. The system is held at rest, then released. Find the acceleration of the system and hence, find the tension in the string.

First we draw a diagram of this system (on whiteboard). Remember to label diagram correctly - the tension on both sides act towards each other.
Since B is a larger mass, we know that mass A will mov...

Answered by • Maths tutor

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A,B and C all lie on the line x^2 + y^2 = 49 where A is on the y axis, B is on the X axis and C is the mid point of the straight-line connecting A and B.

As we know that A and B are on the axis so sub in X=0 and Y=0 into the equation to solve for the co-ordinates A and B.For A 0²+y²=49y= square root of 49 = 7Do the same for B, whic...

Answered by Oliver W. • Maths tutor

3690 Views

How does free radical substitution work?

(This explanation would make use of diagrams on a whiteboard)It is useful to break this down into three steps: 1- the initiation step. Let's take the reaction between Cl₂ and CH₄.

Answered by Tom H. • Chemistry tutor

2550 Views

What is the point of a derivative?

A derivative is a rate of change. For example, let y equal some function of x. Then the derivative of y with respect to x is asking how much y changes with respect to x. We can show this for any x and if ...

Answered by • Maths tutor

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How can i understand fractions?

Fractions can be easily understood by thinking of how to split n numbers of pizzas between d people. Through this we see that everyone gets (n/d) pizzas

Answered by Tomos W. • Maths tutor

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