A block is hung by a string from inside the roof of avan. When the van goes straight ahead at a speed of 24 m/s,the block hangs vertically down. But when the van maintains this same speed around an unbanked curve (radius = 175m) the block swings toward the outside of the curve, then the string makes an angle theta with the vertical. Find theta.
A point charge has a charge of 2.50x10-11C. Atwhat distance from the point charge is the electric potential a)90.0V? b) 30.0V? Take the potential to be zero at an infinitedistance from the charge.
A black body at 7500K consists of an opening of diameter 0.0500mm, looking into an oven. Find the number of photonsper second escaping the hole and having wavelengths between 500nm and 501nm. Hint: use equation 40.6 for
An airplane pilot sets a compass course due west and maintainsan airspeed of 220 km/h. After flying for 0.500 h, she find sherself over a town 120 km west and 20 km south of her starting point. a) Find the wind velocity (magnitude and direction). b) If the wind velocity of 40 km/h due south, in what direction should the pilot set her course to travel due west? Use the same airspeed of 220 km/h.
The answers are:
a) 44.7 km/h, 26.6 deg. west of south
b) 10.5 deg. north of west
Solve the equations and inequalities below, if possible. Check your solutions.