Homework Help: Physics

Posted by Harold on Wednesday, March 4, 2009 at 10:02pm.

A 1400 kg truck goes up a hilly road at a steady 60 km/h. The force of air resistance on the truck is 400 N. If the truck's engine supplies the enrgy to the drive wheels at a rate of 35 kW, what is the slope angle of the road?

I get 7.1 please help, don't really get it.

Physics - drwls, Wednesday, March 4, 2009 at 10:20pm
What are the units of the 7.1 that you get? degrees?

The 60 km/h speed converted to m/s is 16.667 m/s. As the truck goes along the road, it is performing work against friction at a rate of F*V = 400 N * 16.667 m/s = 6666.7 Watts PLUS work against gravity at a rate of M g sin A*V = 228,900 sin A watts

35,000 = 6667 + 228,900 sin A
sin A = 0.1238
A = 7.1 degrees

I agree with your answer, if it was in degrees

Answer this Question

Related Questions

physics - An object is shot from the back of a truck moving at 40 km/h on a ...
physics - A truck of mass 8000 kg is accelerating at 5.0 m/s2 up a hill of ...
physics - A truck engine transmits 28.0 { kW} (37.5 hp) to the driving wheels ...
Physics - A 2600 kg truck traveling at 72 km/h slams on the brakes and skids to ...
physics - a truck with a mass of 2100 kg travels at a constant speed of 75 km/h...
Physics. PLEASE HELP!! - A small car of mass 985 kg is parked behind a small ...
calculus - Two roads intersect at an angle of 48º. A car and truck collide ...
scienc - I'm driving my car of mass 1000 kg at 100 km/hr when I ...
physics - In Fig, a runaway truck with failed brakes is moving downgrade at 160 ...
physics - you find it takes 200N of horizontal force to move an empty pickup ...

For Further Reading

First Name:
School Subject:
Answer: