Wave Energy

Q.

What are the limitations of extracting energy from - (a) the wind? (b) Waves? (c) Tides?

Q.

Define wave energy with an example.

Q.

Which of the given sources of energy is the odd one out?

1. Diesel

2. Coal

3. LPG

4. Wind energy

Q. While calculating heat energy, what should be the unit of time? Second or hours?

Q. Ocean thermal energy is due to:

Q.

How are waves formed ?

1. Gravitational pull of moon

2. Strong Wind blowing on the surface of the sea

3. Uneven heating of sea water

4. None of these.

Q. Question 6
What are the limitations of extracting energy from -
(a) the wind? (b) Waves? (c) Tides?

Q.

What energy transformation takes place in power generation from wave energy?

1. Potential energy to electrical energy

2. Kinetic energy to electric energy

3. Heat energy to electric energy

4. No such energy transformation takes place

Q.

Suppose we take 100 mL of water which has a temperature of 348 K (75°C) and leave it in a room where the temperature is 298 K (25°C). What will happen? Is there any way of collecting all the heat lost to the environment and making the water hot once it has cooled down?

Q.

The principle of Ocean thermal energy conversion is

1. At least a pressure difference of ${120}^{\circ }C$ between the ocean water at the surface and a certain depth.

2. At least a temperature difference of ${120}^{\circ }C$ between the ocean water at the surface and a certain depth.

3. At least a pressure difference of ${20}^{\circ }C$ between the ocean water at the surface and a certain depth.

4. At least a temperature difference of ${20}^{\circ }C$ between the ocean water at the surface and a certain depth.

Q.

What are the disadvantages of wave energy?

1. causes air pollution

2. energy potential from the sea is quite large, but efficient commercial exploitation is difficult

3. is not renewable

4. wave energy is not abundant

Q.

What are the advantages of tidal energy?

Q.

Floating turbine generators are used in the sea to harness ______

1. tidal energy

2. wave energy

3. hydel energy

4. energy from OTEC power plant

Q.

The temperature of water at the bottom of a waterfall will be different from the temperature at the top because:

1. PE lost by water is converted to KE

2. KE lost by water is converted to PE

3. Mass lost by water is converted to Heat Energy

4. PE lost by water is converted to Heat Energy

Q.

If you are making maggie but its taking time because you have kept the temperature slightly lower than whats required , so you want to speed up the process beacuse you are really hungry, you know that whole maggie, water and masala setup weighs 100 gms and specific heat is 0.9, you need 900 calories of heat more to make the maggie , by how much amount you should increase the temperature?

1. 10℃

2. 20℃

3. 30℃

4. 100℃

Q.

What form of energy is possessed by waves?

1. potential energy

2. kinetic energy

3. chemical energy

4. solar energy

Q.

What is OTEC? How does it work? [3 MARKS]

Q.

Floating generators are used in the sea to harness wave energy.

1. wave energy

2. hydel energy

Q. 4kg of hot water at 343 k is added to 6kg of water at 293k.The resultant temp. is 313 k. calculate the heat lost by the hot water and heat gained by the cold water assuming that there is no heat loss to the surroundings.

Q. The two different ways of harnessing energy from ocean are :

1. Tidal Wave, OTEC
2. Geothermal, wave energy device
3. Solar energy, point wave absorber
4. All of the above

Q. a heater rated 1000 W is used to heat 1.6 kg of water at 40°c to its boiling point. Calculate the time in which water starts to boil. Specific heat capacity of water is 4200J/kg/°c.

Q. 272 calories of heat energy is required to heat 0.02 kg of a metal of specific heat capacity 170 cal/kg/°c to a temp.T, if the initial temp. of the metal is 20 °c, calculate the final temp.?

Q.

Why are floating generators used in the sea?

Q. The given figure shows an indicator diagram. During path 1-2-3, 100 cal is given to the system and 40 cal worth work is done. During path 1-4-3, the work done is 10 cal. Then

1. heat given to the system during path 1-4-3 is 70 cal.
2. If the system is brought form 3 to 1 along straight line path 3-1, work done is worth 25 cal
3. along straight line path 3-1, the heat ejected by the system is 85 J
4. The internal energy of the system in state 3 is 140 cal above that in state 1

Q. What is the heat energy taken by 50 g of cold water at 20 degrees C in previous problem?

1. 
   2.1 J
2. 
   21 J
3. 
   210 J
4. 
   2100 J

Q. Energy available from the oceans is:

1. OTE
2. Sea-waves energy
3. Tidal energy
4. All of the above

Q. On a winter day the temperature of the tap water is 20°C whereas the room temperature is 5°C. Water is stored in a tank of capacity 0.5 m³ for household use. If it were possible to use the heat liberated by the water to lift a 10 kg mass vertically, how high can it be lifted as the water comes to the room temperature? Take g = 10 m s⁻².