Answer:
F = 768 N
Explanation:
It is given that,
Speed of the elevator, v = 3.2 m/s
Grain drops into the car at the rate of 240 kg/min, 
We need to find the magnitude of force needed to keep the car moving constant speed. The relation between the momentum and the force is given by :


Since, the speed is constant,



F = 768 N
So, the magnitude of force need to keep the car is 768 N. Hence, this is the required solution.
Wood because it is natural and we use it for furniture but we also burn it for energy.
Answer:
Earth's crust is covered by a densed air blanket called atmosphere. Due to which we feel warm even during night when there is no sun. The air near the atmosphere is less dense compared to the air near our crust. Similarly we can experience high pressure near the atmosphere comparelatively we experience less pressure near crust. The presence of atmosphere above us makes the wind fair sometimes stromy and also helps in pteperation of wind and breezes in earth's surface.
Because no sunlight can penetrate it