Posted by **pam** on Wednesday, July 18, 2012 at 2:51am.

A man on the top of a 40 meter tower directly overhead the road is watching a car moving on a straight road. The car speed makes an angular velocity with respect to the observer in a constant speed of 0.16radian/sec. Find the linear velocity of the car when its position is such that theta=45deg?

- physics -
**bobpursley**, Wednesday, July 18, 2012 at 3:46am
draw the right triangle. Let L be the horizontal length from the base of the tower.

If Theta is the angle of depression from the horizontal (check your drawing), then

Using some geometry, it must be the same angle of the angle of elevation from the car.

TanTheta=40/L

L sinTheta=40 cosTheta

taking the derivative..

SinTheta dL/dt+LcosTheta dTheta/dt=-40sinTheta dTheta/dt

Now, the question asks you to solve dL/dt when Theta=45deg and dTheta/dt=.16

L must = 40 also when theta=45 deg, so you have enough to solve it.

## Answer This Question

## Related Questions

- Physics - A 1100 kg car is moving toward the north along a straight road at a ...
- Physics - A 1100 kg car is moving toward the north along a straight road at a ...
- Physics; help please :) - A car A moves to the left with speed 40 km/h(with ...
- physics - A car is traveling around a circular banked road without friction ...
- physics - a car moving on a straight road with a speed of 20m/s. at t=0 the ...
- Physic - 6. A car is moving along a straight road at 60 mph [26.7 meter/sec ]. ...
- Physics Help, Please! - When a car goes around a curve (without skidding), on a...
- PHYSICS - A car is traveling around a circular banked road without friction ...
- physics - car moving on a straight road covers a distance of 1.5 km due east in...
- Physics - A car with a mass of 900 kg moves along a road at a 89 km/hour at ...

More Related Questions