A 2000-kg railway freight car coasts at 4.4 m/s underneath a grain terminal, which dumps grain directly down into the freight car. If the speed of the loaded freight car must not go below 3.0 m/s, what is the maximum mass of grain that it can accept?

933. 3kg

Explanation:

We are given that

Mass,m=2000 kg

Initial speed,u=4.4 m/s

We have to find the maximum mass of grain if the speed of loaded freight car must not go below 3.0 m/s.

Final speed,v=3 m/s

By conservation of momentum

Initial momentum=Final momentum

Substitute the values

Mass of freight loaded car=2933.3 kg

Mass of grains=2933.3-2000=933.3 kg

Hence, the maximum  mass of grains that it can accept=933.3 kg

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