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What is the difference between velocity and speed?

Both the speed and the velocity show us how fast something is moving (the rate at which it changes its position). However, velocity is a vector quantity, which means it also gives us information about the di...
BS
Answered by Bozhidara S. • Physics tutor
3743 Views

Describe how you could find the density of a cube of metal? (4 marks) (Example from GCSE bitesize)

Think of key words in the questions to help solve it. For example in this question we need to consider density and the fact that the object is a cube. 2) Remember the equation of density which is : Density =...
BA
Answered by Branwen A. • Physics tutor
4795 Views

What is the 'lock and key' hypothesis?

A reaction can only be catalysed (sped up) if an enzyme's active site matches the shape of its substrate molecules- the substrate fits into the active site like a key into a lock. This shape is highly specif...
EE
Answered by Emily E. • Biology tutor
3374 Views

An apple is suspended a string and a spring in parallel. When the string is cut, the apple falls, and the spring stretches and contracts repeatedly as the apple bounces. Describe the energy conversions that occur during this process.

When the string is cut:Gravitational potential energy is converted to kinetic energy.Kinetic energy is converted to elastic potential energy.Elastic potential energy is converted to kinetic energy (and heat ...
DS
Answered by Dan S. • Physics tutor
3968 Views

What are the possible ways to find the roots from a quadratic equation?

quadratic equation where the coefficients of the quadratic equation: ax^2 + bx + c are substituted into the formula: [-b +- (b^2 - 4ac)^0.5] / 2a. The roots are what x equalscompleting the square where the c...
SB
Answered by Sophie B. • Maths tutor
3926 Views