What is true for this Sankey diagram?
The overall efficiency of the process is 10%.
Generation and transmission losses account for 55% of the energy input.
Useful energy accounts for half of the transmission losses.
The energy loss in the power station equals the energy that leaves it.
Which feature of the graph helps explain the greenhouse effect?
Infrared radiation is absorbed at specific wavelengths.
There is little absorption at infrared wavelengths.
There is substantial absorption at visible wavelengths.
There is little absorption at UV wavelengths.
The atmosphere is transparent to all solar radiation.
The atmosphere absorbs infrared radiation from the ground.
The atmosphere scatters red light more than blue light.
Clouds in the atmosphere prevent absorption of infrared radiation.
What are the ideal properties of the moderator atoms and the control atoms in terms of neutron absorption?
the surface of the Earth.
the mean distance from the Sun of the Earth’s orbit around the Sun.
the surface of the Sun.
10km above the surface of the Earth.
water of density 103kgm–3 falls through an average height of 100m. The volume of water flowing through the pipes per second is 10m3s–1. What is the maximum power generated?
kinetic energy is removed from the neutrons.
kinetic energy is given to the neutrons.
some neutrons are absorbed.
extra neutrons are added.
greater than the rate of consumption of the resource.
less than the rate of consumption of the resource.
always equal to zero.
decreasing as the resource is consumed.
nuclear, geothermal, coal
nuclear, coal, geothermal
coal, geothermal, nuclear
coal, nuclear, geothermal
can be effective in any location.
can be used continuously.
have low initial set-up costs.
are more environmentally friendly when in use.
Decommission nuclear power plants
Replace the use of coal and oil with natural gas
Use combined heating and power (CHP) systems
Use hybrid motor vehicles
absorb neutrons to shut down the reactor.
speed neutrons up to increase the rate of energy production.
slow neutrons down to decrease the rate of energy production.
slow neutrons down to make a chain reaction more likely.
absorb incoming radiation from the Sun.
transmit the incoming radiation from the Sun and radiation from the Earth.
reflect incoming radiation from the Sun.
transmit incoming radiation from the Sun and absorb outgoing radiation from the Earth.
A body X of emissivity e is at temperature T1. X is inside a box whose walls act as a black body of temperature T2. T1 is greater than T2.
What is the net intensity of radiation leaving body X?
What are the principal means for losing energy for a hot rock resting on the surface of the Moon?
I and II only
I and III only
II and III only
I, II and III
The fuel has high energy density.
Supplies of nuclear fuels are unlimited.
Greenhouse gas emissions are significant.
Waste products are not significant.
How do the temperature and the emissivity of X compare with the temperature and the emissivity of Y?
The graph shows the emission spectrum for a black body at absolute temperature T1.
Which graph shows the emission spectrum for the same black body at an absolute temperature T2 where T2 > T1? The original graph is shown as a dotted line.