In the boiler of a steam engine, there is a firebox where coal is shoveled into. The coal is kept burning at a very high temperature, and is used to heat the boiler to boil water producing a high pressure steam. The high-pressure steam expands and exits the boiler via steam pipes into the steam reservoir, the steam is then controlled by a slide valve to move into a cylinder to push the piston. The pressure of the steam energy pushing the piston turns the drive wheel in a circle, creating motion for the locomotive.

Correct Option: C

In the boiler of a steam engine, there is a firebox where coal is shoveled into. The coal is kept burning at a very high temperature, and is used to heat the boiler to boil water producing a high pressure steam. The high-pressure steam expands and exits the boiler via steam pipes into the steam reservoir, the steam is then controlled by a slide valve to move into a cylinder to push the piston. The pressure of the steam energy pushing the piston turns the drive wheel in a circle, creating motion for the locomotive.

Geothermal energy is thermal energy generated and stored in the Earth. The Geothermal energy of the Earth’s crust originates from the original formation of the planet (20%) and from radioactive decay of minerals (80%).Current worldwide installed capacity is 10,715 megawatts (MW), with the largest capacity in the United States (3,086 MW), Philippines, and Indonesia.

Correct Option: D

Geothermal energy is thermal energy generated and stored in the Earth. The Geothermal energy of the Earth’s crust originates from the original formation of the planet (20%) and from radioactive decay of minerals (80%).Current worldwide installed capacity is 10,715 megawatts (MW), with the largest capacity in the United States (3,086 MW), Philippines, and Indonesia.

Electric fuse wire is an alloy made of tin (63 % & lead 37 %. The cross sectional area determines the melting point at a certain current. Alloys (e.g. tin/ lead) are used due to their ‘eutectic’ action -i.e. the resulting combination of good conductivity (due to the tin) with a low melting point due to the lead).

Correct Option: B

Electric fuse wire is an alloy made of tin (63 % & lead 37 %. The cross sectional area determines the melting point at a certain current. Alloys (e.g. tin/ lead) are used due to their ‘eutectic’ action -i.e. the resulting combination of good conductivity (due to the tin) with a low melting point due to the lead).

The operation of a rocket illustrates the conservation of momentum. Just before launching, the momentum of the rocket is zero. When the rocket is fired, it forces a jet of hot gases with a high velocity through the nozzle. The jet of gases acquires a momentum downwards. Hence, the rocket acquires a momentum of equal magnitude in opposite direction. Thus the rocket moves upwards.

Correct Option: A

The operation of a rocket illustrates the conservation of momentum. Just before launching, the momentum of the rocket is zero. When the rocket is fired, it forces a jet of hot gases with a high velocity through the nozzle. The jet of gases acquires a momentum downwards. Hence, the rocket acquires a momentum of equal magnitude in opposite direction. Thus the rocket moves upwards.

Pure water is actually an extremely poor conductor, but saturated salt water is a good conductor. The saltier the water, the better the conductance. The reason it conducts electricity is because the NaCl (sodium chloride) breaks apart into a positively charged Na+ and a negatively charged Chlorine Cl-. When current is applied, it is easily conducted by the highly charged ions.

Correct Option: C

Pure water is actually an extremely poor conductor, but saturated salt water is a good conductor. The saltier the water, the better the conductance. The reason it conducts electricity is because the NaCl (sodium chloride) breaks apart into a positively charged Na+ and a negatively charged Chlorine Cl-. When current is applied, it is easily conducted by the highly charged ions.