the efficiency of cell is 75° if it's supplies current true an external resistance 9.0ohms find the value external resistance.​

Ajogger accelerates from rest to 4.86 m/s in 2.43 s. a car accelerates from 20.6 to 32.7 m/s also in 2.43 s. (a) find the magnitude of the acceleration of the jogger. (b) determine the magnitude of the acceleration of the car. (c) how much further does the car travel than the jogger during the 2.43 s?

An insurance company wants to know if the average speed at which men drive cars is higher than that of women drivers. the company took a random sample of 27 cars driven by men on a highway and found the mean speed to be 72 miles per hour with a standard deviation of 2.2 miles per hour. another sample of 18 cars driven by women on the same highway gave a mean speed of 68 miles per hour with a standard deviation of 2.5 miles per hour. assume that the speeds at which all men and all women drive cars on this highway are both approximately normally distributed with unknown and unequal population standard deviations.

Amodel rocket with a mass of 0.212 kg is launched into the air with an initial speed of 84 m/s. how much kinetic energy will the rocket have at a height of 214 m? assume there is no wind resistance. 634 j 303 j