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Explain in terms of specific heat capacity why a hot water bottle is good at heating a bed.

Water has a very high specific heat capacity, it is fair to assume bed-sheets and bedding items have a much lower specific heat capacity. If an object has a high temperature and is in surroundings at a lower...
JL
Answered by Jessica L. Physics tutor
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Draw a freebody diagram showing the forces acting on a box sat on a table

The first thing to note is that the book is sat on the table, so it is stationary. From newtons laws, we know it must have 0 total force acting on it. Every object on the earth feels a force downwards due to...
RS
Answered by Robin S. Physics tutor
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(A-level but box won't let me change it from GCSE) A particle of charge q and initial speed v is stopped by a potential difference V in distance d and time t. What was its initial momentum?

Define p=momentum, E=electric field.Firstly we know that:1) ∆p/∆t = F - definition of momentum2) F = Eq - force on particle in an electric field caused by a voltage3) E = V/d - definition of electric field o...
GT
Answered by Greta T. Physics tutor
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A car travelling at 14 m/s has to make an emergency stop so applies the brakes and it takes 1.5s to become stationary. What distance has the van travelled in that time?

Assuming constant deceleration we can use the equation s = t(u+v)/2, where u=14m/s, v=0m/s and t=4s. Inputting these values we have that the distance travelled s = 1.5(14)/2 = 21/2 = 10.5m u = the starting v...
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Answered by Caitlin J. Physics tutor
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What are the similarities and differences between an elastic and an inelastic collision?

In both an elastic and inelastic collision momentum is conserved, however in an elastic collision the total kinetic energy is the same before and after the collision. In an inelastic collision kinetic energy...
HG
Answered by Henry G. Physics tutor
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