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If a particle of mass m is launched vertically upwards from the ground with velocity u m/s, how long will it take to return to the ground in terms of m, u and g?

Taking upwards to be positive, and using the 'suvat' equation s=ut+1/2at² we know that u=u, a=-g and s=0 when the particle returns to the ground. Then we solve for t:
0=ut-1/2gt²

Answered by Jackie V. • Maths tutor

3329 Views

Use the substitution u=x^2-2 to find the integral of (6x^3+4x)/sqrt( x^2-2)

First use the substitution to find du/dx which is 2x. From this we now know that dx= du/2x (just re-arranging.) Substituting that into the integral we now get (6x³+4x)/ (sqrt (u) x 2x) du. Canc...

Answered by Khalil S. • Maths tutor

10129 Views

Explain opportunity cost

Opportunity cost is the cost of sacrificing the next best alternative to the activity under consideration. In order to explain this I will use a literal example. You are going to watch a football match. T...

Answered by Edward H. • Economics tutor

2472 Views

Identify the differences between motor and sensory neurons in terms of features and function.

Motor neurons have a cell body, short dendrites and a long axon. Their function is to conduct impulses to an effector (muscle or gland).Sensory neurons, on the other hand, have a cell body, long dendrites...

Answered by Michelle M. • Biology tutor

27789 Views

How do I plan an answer to a close reading question in my exam?

Planning in an exam is really important. It will help you settle into the exam, cover the assessment objectives and write a clear and interesting answer to the question. Everyone approaches planning diffe...

Answered by Ruth P. • English tutor

1966 Views