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What is terminal velocity?

Terminal velocity is the final velocity an object achieves during freefall through a medium under the influence of gravity and upthrust from the medium. For example, dropping a tennis ball from a plane. The ...
CJ
Answered by Chenyang J. • Physics tutor
5060 Views

What is the density of a rock (mass 75g) submerged in water which displaced by a volume of 37.5cm^3? SI units

75g = 0.075kg/ 37.5cm 3 = (37.5 divided by 100 3 ) m 3 = 3.75 10 -5 m 3 / density = mass divided by volume/ 0.075 divided by 3.75 10 -5 = 2000kg/m 3
MH
2941 Views

Explain the role of the moderator in a fission reaction.

slows neutrons/reduces KE of neutrons so that neutrons can be absorbed by the U-235 nucleus to cause fission to release kinetic energy. (nuclear reactor and energy)
RJ
Answered by Rishi J. • Physics tutor
3284 Views

What name is given to the phenomena which results in longer wavelengths of light being observed from distant galaxies and why does this occur?

Red shift; this phenomena occurs as a result of the distant galaxies moving away from the Earth and all the wavelengths of electro-magnetic radiation being emitted are 'stretched' towards to the longer wavel...
WB
Answered by William B. • Physics tutor
2946 Views

Why are some electromagnetic waves harmful to humans?

Electromagnetic (EM) waves form the electromagnetic spectrum with a range of wavelengths. EM waves that have wavelengths shorter than those of visible light include ultraviolet light, X rays and gamma rays, ...
KH
Answered by Keval H. • Physics tutor
9627 Views