The wavelength of waves produced on the surface of water is 20 cm. If the wave velocity is 24 m/s, calculate:
i) State the purpose of a fuse in an electric circuit. Name the material used for making a fuse wire.
ii) Mention two factors on which the internal resistance of a cell depends.
State the main difference between a step-up and step-down transformer.
Step- up transformer |
Step-down transformer |
|
1. Number of turnsin secondary coil is less than in primary coil. Ns/NP < 1 |
2. Voltage is increased and current is decreased. |
2. Voltage is decreased, current is increased. |
In winter, the weather forecast for a certain day was ‘severe frost’. A wise farmer watered his fields the night before to prevent frost damage to his crops. Why did he water his fields?
10125 J of heat energy boils off 4.5 g of water at 100oC to steam at 100o C. Find the specific latent heat of steam.
A ball of mass 0.20 kg is thrown vertically upwards with an initial velocity of 20 m/s. Calculate the maximum potential energy it gains as it goes up.