Answers by visitors named: dfrwls
The total resistance of the wires is Rwire = 4.2*0.05 = 0.21 ohms. The current flowing in the wires when delivering 1.2*10^6 W is P/V = 1.2*10^6 W/1200 = 1000 A Poower lost in wires = I^2*Rwire = 210,000 W With a 100:1 stepup transformer, I is 100 x less....
13 years ago
The equation you have to solve is 80 sin 30 t - (g/2) t^2 = -150 which can be rewritten 40 t - 4.9 t^2 = -150
13 years ago
The horizontal initial velocity does not affect the time to hit the ground. You should know how to compute how long it takes to fall 60 m, since you are in an "honors" class. Multiply that time by 6.5 m/s for part 2.
13 years ago