A man of mass 85 kg runs up a flight of stairs of height 4.6 m in a time period of 12 s.
a) Calculate the man’s power rating when doing this.
b) A girl achieves a power rating of 70% of the man’s power rating wh en she scales the stairs in a time of 9.6 s. Calculate the mass of the girl.

The motor m applies a time-varying force of f (200 t) n, where t is in seconds. box b with mass 200 kg starts from rest, and the coefficients of kinetic and static friction are 0.2 and us 0.3 the acceleration due to gravity is g 9.8 m/s2 b 300 a) find the time ' when the box starts to move. b) calculate the speed of the crate at 3 s c) calculate the power delivered by the motor at t 3 s

Aprisoner is forced to go into one of three rooms, but he can choose which room. the first room is ablaze with fire. the second one is rigged with explosives that will go off as soon as he enters. the third contains a pair of lions who haven't eaten in years. which room should he choose to survive?

Identify some abiotic characteristics of the tundra biome.