Problem from relative velocity

A Boat covers certain distance between two spots in a river taking t1 hrs going downstream and t2 hrs going upstream. What time will be taken by boat to cover same distance in still water? posted by STUTI Answer: Incoming search terms:relative velocity...

The problem of a rock thrown vertically up

A rock is thrown vertically upward from the ground with an initial speed 15m/s. a. how high does it go b. how much time is required for the rock to reach its maximum height? c. what is the rock’s height at t=2.00s? (Posted by Merhawi) Answer: (a) u=15m/s a=-10m/s2 v=0 m/s [...]

The problem of a rock thrown vertically up

A rock is thrown vertically upward from the ground with an initial speed 15m/s. a. how high does it go b. how much time is required for the rock to reach its maximum height? c. what is the rock’s height at t=2.00s? (Posted by Merhawi) Answer: (a) u=1...

The problem of a rock thrown vertically up

A rock is thrown vertically upward from the ground with an initial speed 15m/s. a. how high does it go b. how much time is required for the rock to reach its maximum height? c. what is the rock’s height at t=2.00s? (Posted by Merhawi) Answer: (a) u=1...

Homework from Projectile Motion

A projectile is projected at an angle theta with horizontal with speed u . If air resistance is taken in account , the angle with vertical at the time of hitting the ground will be a)more than (90 + theta) b)less than (90 – theta) c)(90 + theta...

A simple numerical on momentum

Car mass is 1200 kg moving velocity is 108 km/hr. On applying brakes velocity reduced to 36 km/hr. Find change in momentum? (posted by Aditi) Answer: m=1200 kg u=108 x 5/18=30m/s v=36×5/18=10m/s Change in momentum = m(v-u) = 1200 x (30-10)=1200 ...

A simple numerical on momentum

Car mass is 1200 kg moving velocity is 108 km/hr. On applying brakes velocity reduced to 36 km/hr. Find change in momentum? (posted by Aditi) Answer: m=1200 kg u=108 x 5/18=30m/s v=36×5/18=10m/s Change in momentum = m(v-u) = 1200 x (30-10)=1200 ...