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Assuming the Earth is a perfect sphere of radius R. By how much would your mass (m), as given by a scale, change if you measured it on the north pole and on the equator?

The key observation here is that the Earth is spinning (angular velocity w) and so are you. The scale will give one number or another depending on the force that you exert on it, and by Newton's 3rd Law t...

Answered by Javier P. • Physics tutor

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what is the density of a rock mass (0.05kg), submerged in water which diplaced by a 25cm^3 volume?

Answer:Mass (m)= 0.05kgVolume = 25cm^3Density=mass/Volume= 0.05kg/25cm^3=2000kg/m^3

Answered by Fria H. • Physics tutor

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A particle of mass 5kg is moving in circular motion with a time period of 2 seconds. The radius of the circle is 10m. What is the centripetal force on the particle

The angular velocity is equal to 2 times pi divided by the time period. So we have an angular velocity of pi radians per second. The centripetal force is given by mass times the radius times the angular v...

Answered by • Physics tutor

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Alex's rocket lands after 4.56s and Billy's lands after 5.21s. What was the initial (maximum) vertical velocity of both of their rockets as they left the launchpad to 3s.f.?

Application of suvat equation v=u+at. Students acknowledge that at the rocket's maximum height it will have a velocity of 0. They also realise that the time to reach thi s point from launch is half ...

Answered by • Physics tutor

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Draw a diagram of the forces acting on the rocket as it flies vertically upwards, the rocket is flying through air not a vacuum (it's not in space yet!)

They should draw a vague rocket shape pointed upwards. It will have one arrow pointing straight down through the rocket marked "gravity", "g", or "g=9.81kg m/s^2" etc. Anothe...

Answered by • Physics tutor

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