Answer: 1026s, 17.1m
Explanation:
Given
COP of heat pump = 3.15
Mass of air, m = 1500kg
Initial temperature, T1 = 7°C
Final temperature, T2 = 22°C
Power of the heat pump, W = 5kW
The amount of heat needed to increase temperature in the house,
Q = mcΔT
Q = 1500 * 0.718 * (22 - 7)
Q = 1077 * 15
Q = 16155
Rate at which heat is supplied to the house is
Q' = COP * W
Q' = 3.15 * 5
Q' = 15.75
Time required to raise the temperature is
Δt = Q/Q'
Δt = 16155 / 15.75
Δt = 1025.7 s
Δt ~ 1026 s
Δt ~ 17.1 min
Answer:
P = 5880 J
Explanation:
Given that,
The mass of the block, m = 30 kg
The block is sitting at a height of 20 m.
The block will have gravitational potential energy. The formula for gravitational potential energy is given by :

So, the required potential energy is equal to 5880 J.
Light waves are reflected from front and back surfaces of the thin films and constructive interference between the two reflected waves occurs in different places for different wavelengths. Light shining on the upper surface of the thin film with thickness t is partly reflected at the upper surface (path abc). Light transmitted from the upper surface is partly reflected at the lower surface (path abdef). The two reflected waves come together at point P on the retina of the eye. Depending on the phase relationship, they may interfere constructively or destructively. Different colors have different wavelengths, so the interference may be constructive for some colors and destructive for others.
No one can really tell exactly how old the universe is. However, scientists have attempted to estimate the time by using the concept of Doppler effect which depends on the frequency of the stars and their relative velocities. From literature, the universe is about 13.82 billion years old. Thus, the age of the universe is 13.82×10⁹ times longer than a year.
Answer:
Option (A)
Explanation:
Diffusion is defined as the transfer of particles such as ions or molecules from a higher concentration region to a lower concentration region.
Osmosis is a special type of diffusion in which the solvents such as water are allowed to move from a region of higher to a lower concentration through a layer of a semi-permeable membrane. This is an energy-independent process and occurs along the concentration gradient.
Thus, the correct answer is option (A) that is true for both osmosis and diffusion.