# I need help with this i am lost

#### bc33rocks

1.Sand from a stationary hopper falls on a mov-
ing conveyor belt at the rate of 4 kg/s, as
shown in the figure. The belt is supported by
frictionless rollers and moves at 1.07 m/s un-
der the action of a horizontal external force
supplied by the motor that drives the belt.
Find the sand’s rate of change of momen-
tum in the horizontal direction. Answer in
units of N.

2. i know the rate of change of momentum is equal to the force but i need help figuring out that i really just need help getting started

3.

Related Introductory Physics Homework Help News on Phys.org

#### LowlyPion

Homework Helper
1.Sand from a stationary hopper falls on a mov-
ing conveyor belt at the rate of 4 kg/s, as
shown in the figure. The belt is supported by
frictionless rollers and moves at 1.07 m/s un-
der the action of a horizontal external force
supplied by the motor that drives the belt.
Find the sand’s rate of change of momen-
tum in the horizontal direction. Answer in
units of N.

2. i know the rate of change of momentum is equal to the force but i need help figuring out that i really just need help getting started
3.

Welcome to PF.

Well what is the change in momentum?

Momentum after - momentum before? I can't see your picture, but I suppose it falls vertically. So the final speed in X is what? The initial speed in X is what and what is the rate of sand mass in 1 sec? ...

### Physics Forums Values

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving