M1 force and motion question help please!

Hi, this is the question Im stuck on, I seem to forget the right method.

A girl of mass 48kg stands in a lift that is going upwards. The lift initially acclerates at 2ms^-2 and then travels at a constant speed of 1.5ms^-1. Finally, the lift acclerates at 3ms^-2. The normal reaction of the floor of the lift on the girl is RN.

Write down the value of R while the lift is travelling at constant speed. - is it just 48*9.8?

Calculate the value of R when the lift is acclerating at 2ms^-2, and calculate the value of R when the lift is decelerating at 3ms^-2.

Thanks for the help in advance, quick replies would be grealy appreciated!

Reply 1

RandomStudentWho

Original post by mcyan

hi, this is the question im stuck on, i seem to forget the right method.

A girl of mass 48kg stands in a lift that is going upwards. The lift initially acclerates at 2ms^-2 and then travels at a constant speed of 1.5ms^-1. Finally, the lift acclerates at 3ms^-2. The normal reaction of the floor of the lift on the girl is rn.

Write down the value of r while the lift is travelling at constant speed. - is it just 48*9.8?

Calculate the value of r when the lift is acclerating at 2ms^-2, and calculate the value of r when the lift is decelerating at 3ms^-2.

Thanks for the help in advance, quick replies would be grealy appreciated!