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A rocket is at rest on the moon, where g=2 m/s^2. It has a total mass of 1500kg, 1000kg of which is fuel. Fuel is propelled out of the bottom of the rocket at 400m/s, at a rate of 10kg/s. Derive an equation to show its upwards acceleration over time.

The first step is to construct a force diagram of the rocket, which has two forces acting on it; its weight (W) and thrust (T) in opposite directions. T can be calculated by combining the equations F=ma a...

Answered by Alexander B. • Oxbridge Preparation tutor

2241 Views

Describe and explain how blood glucose levels are controlled following a meal.

Following a meal, the levels of glucose in the blood will increase. This increase in the level of glucose needs to be controlled, otherwise the levels of glucose will become too high and someone could end...

Answered by Dr Usama A. • Biology tutor

3321 Views

How can I use the Pythagoras' Theorem to work out the length of a missing side of a triangle?

We have the triangle ABC. AB = 3 BC = 4 AC = ?
By inputting these numbers into the Pythagoras' Theorem, we can out the length of the missing side (AC).
a²+ b² = c²

Answered by Zhane E. • Maths tutor

3585 Views

When do we use the imperfect tense and how is it formed?

The imperfect tense is used for continuous, ongoing actions in the past. It is often used for descriptions (when we are 'setting the scene') in the past, and it is used when we talk about things that we '...

Answered by James H. • French tutor

2289 Views

A curve has equation y = 20x −x2 −2x3 . (A) Find the x-coordinates of the stationary points of the curve.

Firstly, differentiate the equation to find dy/dx.
dy/dx = 20 - 2x - 6x²
As dy/dx represents the gradient, we know that for a stationary point the gradient must be zero, hence for the...

Answered by Bradley W. • Maths tutor

6129 Views