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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. ...

Answered by Sam G. • Physics tutor

20875 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.

Answered by Odin G. • Physics tutor

2290 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 freq...

Answered by Molly C. • Physics tutor

12489 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 10²²kgThe Moon has a radius, R_M = 1.74 x 10m
We want to determine the gravitational constant for the Moon's surface to then calculat...

Answered by Guy B. • Physics tutor

2696 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^-34Js,m = mass of object,v = object's velocity,
Mass of proton m_p = 1.6...

Answered by Haider A. • Physics tutor

9895 Views