Which of the following electric device use minimum energy? 1. LED of 3W used for 6 hours.
2. water motor 1 HP used for 20 minutes.
3. heater of 1200W used for 3 minutes.
4. bulb of 60W used for 1 hour. ​

Current 1 of 8.4 a runs for 240 seconds and then stops. current 2 is 10.5 a. how long does current 2 have to un to deliver the same amount of charge as current 1? 88.28 192 s 2016 s 21,000 s

The position of a crate sliding down a ramp is given by x=(0.05t^3) m, y=(1.7t^2) m, z=(6−0.85t^5/2) m, where t is in seconds. (a) determine the magnitude of the crate's velocity when t = 2 s. (b) determine the magnitude of the crate's acceleration when t = 2 s.

What is a subatomic particle with a negative charge and very little mass?