You have designed a tennis ball cannon with a muzzle velocity of 50 m/s. you want to land a tennis ball in a swimming pool 200 m away. at what angle to the horizontal do you need to aim the gun? round your answer to the nearest degree.

when a device is used in a circuit in which the voltage is 81 v, the current flowing through the device is 3 a. what is the resistance of the device?

a. 27 ω

b. 40.5 a

c. 243 ω

d. 243 a

the correct answer is a. 27

continuous conducting path for current, power supply

t = 1/400 h   ⇔ 0.0025 h ⇔ 9s ⇔ 0.15 m

any of the answers are correct.