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a solar cell of area 2m^2 has maximum a power output per unit area of 20W/m^2 . if four solar cells are used together at once, how much energy is release in 2 mins at max power output?

max output of 1 cell = 20x2= 40w , so four cells gives 4x40 = 160w so if it gives 160 joules a second then in 2 mins it will put out 160 x (2x60) = 19200 joules

Answered by Merlin B. • Physics tutor

1402 Views

An electron is emitted from a cathode in an electron gun, with a potential difference of 150kV. Find the velocity of the electron after it is accelerated and find the De Broglie wavelength.

V=J/C1.602×10^-19 ×150×10^3=1/2×m×v^2
v=(2×1.602×10^-19×150×10^3/9.11×10^-31)^1/2v=2.29×10^8 m/sλ=h/pλ=6.63×10^-34/2.29×10^8 × 9.11×10^-31λ=3.17×10^-12

Answered by Adam C. • Physics tutor

1362 Views

How does heat transfer through convection work?

Convection is transfer of energy through movement of liquid particles. Let us take some steps back and revise a number of principles. First of all, you should remember the concept of density. If two parts...

Answered by Alireza M. • Physics tutor

1628 Views

A footballer kicks a ball vertically upwards. Initially, the ball is stationary. His boot is in contact with the ball for 0.050s. The average resultant force on the ball during this time is 180N. The ball leaves his foot at 20m/s. Calculate the impulse

Impulse is Force x TimeThe force has been given as 180N. The time that the foot was in contact with the ball was 0.05sImpulse=FxtImpulse=180x0.05Impulse= 9Ns

Answered by Sophia A. • Physics tutor

8278 Views

Name and describe both of Kirchhoff's laws.

The Loop rule, this states that the sum of the potentials in a loop must be equal to 0.The Junction rule, this states that the sum of the current entering the junction must be equal to the sum of the curr...

Answered by Boris B. • Physics tutor

1489 Views