What is the time required for an object starting

from rest to fall freely 500. meters near Earth's

surface?

(1) 51.0 s (3) 10.1 s

(2) 25.5 s (4) 7.14 s

Add a nail in CuSO4 Sodium, the colour of CuSO4 disappears why?

Scientist suggest that galaxies are moving away from Earth due to A. Dark energy B. Doppler shift C. Energy D. Solar energy

What is the change in internal energy if 20 J of heat is released from a system and the system does 50 J of work on the surroundings? A.-80 J B.-20 J C. 80 J D. 20 J

The Curiosity Rover has recently landed on Mars and likes to send Twitter updates on its progress. If a tweet is posted 15 minutes after it was sent, how far is Curiosity from Earth?

Tanner is running his finger around the top of a crystal glass with a natural frequency of 1100 hertz. If Tanner can cause the glass to resonate, it could create a high-pitched sound and shatter.

A bird has a kinetic energy of 3 J and a potential energy of 25 J. What is the mechanical energy of the bird?

Material A has a higher thermal conductivity than Material B. Which material will transfer energy by conduction faster?

an electrical iron box having power 400w is operated in 10hours. what will be the energy consumed by the device in commercial unit?

True or False: If your gas pedal jams, you should turn the key to lock to lock the steering wheel.

Pylon cables in the National Grid have some resistance. Power (watts) = Current2 (amperes) x Resistance (ohms) Looking at the power equation above, can you explain why transmitting electricity at a very high voltage is beneficial?