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A boy with a mass of 50kg is sitting on a seesaw. He is sitting 2m from the pivot. He has a friend who weighs 40kg, how far away from the pivot must she sit to balance the seesaw? (gravitational accelleration (g) = 10m/s2)

This is a question relating to turning forces, known as moments . For the seesaw to be balanced the moment caused by the 50kg boy must be equal and opposite to the moment caused by the 40kg girl. A moment is...
SG
Answered by Sam G. • Physics tutor
22683 Views

What is the definition of a moment?

A moment is the product of force and the perpendicular distance from the pivot to the line of action of the force.
OG
Answered by Odin G. • Physics tutor
3045 Views

How does the photoelectric effect (gold leaf experiment) demonstrate the particle nature of light?

A certain amount of energy is required to eject an electron from a metal surface. The gold leaf experiment shows that only light above a certain threshold frequency is able to eject electrons. If the frequen...
MC
Answered by Molly C. • Physics tutor
13928 Views

A student has a mass of 80kg. How much would the student weigh on the surface of the Moon?

The Moon has a mass, M M = 7.35 x 10 22 kgThe Moon has a radius, R M = 1.74 x 10m We want to determine the gravitational constant for the Moon's surface to then calculate the weight of the student using Newt...
GB
Answered by Guy B. • Physics tutor
3465 Views

Electrons moving in a beam have the same de Broglie wavelength as protons in a separate beam moving at a speed of 2.8 × 10^4 m/s . What is the speed of the electrons?

de Broglie wavelength formula: λ = h/mv, whereλ = wavelength,h = Planck's Constant = 6.626 x 10 -34 Js,m = mass of object,v = object's velocity, Mass of proton m p = 1.6726219 × 10 -27 kg,Velocity of proton ...
HA
Answered by Haider A. • Physics tutor
10774 Views