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Given the rate of thermal energy transfer is 2.7kW, the volume of the water tank is 4.5m^3, the water is at a temperature of 28oC, density of water is 1000kgm-3 & c=4200Jkg-1K-1. Calculate the rise in water temperature that the heater could produce in 1hr

The equations needed to solve this problem are outlined below. E = mc(T₂ - T₁) d = m/v P = E/tYou first need to work out the mass of the water. m = 1000 x 4.5 = 4500kg You then need ...

Answered by Jasmine B. • Physics tutor

2320 Views

Find current and voltage across resistors R1 and R2, when they connected in parallel and in series. A 12V battery is connected, R1=4Ω and R2=3Ω.

First of all, we try to find a circuit where resistors are connected in parallel. When resistors are connected in parallel, the voltage across each resistor is exactly the same, V1 = V2 = 12 V. On t...

Answered by Egle A. • Physics tutor

33210 Views

Jane drops a football from the roof onto the ground below. The ball weighs 0.8kg and the distance the ball falls is 5m. Assuming there are no external forces acting on the ball, what speed will the ball be travelling at just before it hits the ground?

As the ball falls from a height to the floor, the gravitational potential energy stored in the ball will be converted to kinetic energy.The gravitational potential energy of the ball can be calculated usi...

Answered by Katie O. • Physics tutor

1654 Views

A ball is dropped from rest at a height of 2 metres. Assuming acceleration due to gravity (g) is 10m/s^2 calculate the velocity of the ball just before it hits the floor.

Using the equation V² = U² + 2as, where V = final velocity, U = initial velocity, a = acceleration, s = displacement, we can substitute in the values given in the question t...

Answered by Phil B. • Physics tutor

1926 Views

When a particle travels in a circle of radius r, at constant speed v, what is its acceleration

v²/r, towards the center of the circle.Remember that acceleration is the rate of change of velocity, not merely of speed. This means that the change in direction is im...

Answered by • Physics tutor

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