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Which unit is equivalent to J kg^-1? a) m s^-1 b) m s^-2 c) m^2 s^-1 d) m^2 s^-2

When working out unit equivalences the most straightforward approach is to use formulas (often in the data booklet) to help reach a correct answer. We start by looking at Joules; knowing a Joule is a unit of...
SK
Answered by Samuel K. • Physics tutor
29498 Views

What are the differences between microwaves and radio waves? How does this effect what we use them for?

Microwaves and radio waves are both used for communication purposes. Microwaves have a higher frequency, and therefore a smaller wavelength. Because of this, microwaves can travel through the Earth's atmosph...
MR
Answered by Madeleine R. • Physics tutor
23090 Views

A tennis ball is hit over a net with a speed of 45ms^-1 and has a mass of 30g. Calculate the kinetic energy of tennis ball.

K=0.5 mv^2 K=0.5 0.03*(45^2) K=30.4J
LM
Answered by Liam M. • Physics tutor
3984 Views

What is the amplitude and period of y=3sin(5x)?

Amplitude of a periodic function is the maximum height it reaches above the centre line (or the lowest). This expressed in the equation as '3'. If the 3 was not there, then the sin wave would have an amplitu...
MR
Answered by Madeleine R. • Maths tutor
7166 Views

A rock has a mass of 100g and it is thrown across a pond at a speed of 30ms^-1. Calculate the de Broglie wavelength of the rock and explain whether you can see the wave produced.

λ=h/p λ=h/mv λ= 6.63 10^-34/0.1 30 λ= 2.21*10^-34m We cannot see the rock's de broglie wave because its wavelength is much smaller than that of the visible spectrum
LM
Answered by Liam M. • Physics tutor
3762 Views