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3 resistors, R1, R2 and R3 are attached in parallel across a 6V cell with resistances 3, 4 and 5 Ohms respectively. Calculate the current across each resistor.

First off draw the circuit. The voltage across each resistor is equal (i.e. 6V). From here we just have to use Ohm's law (V = I x R) to calculate the currents across each resistor. This gives us: R1; 6V = I ...
MP
Answered by Marcus P. • Physics tutor
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If a car drives at 5 ms^-1 for 10 seconds and then 6 ms^-1 for 5 seconds, how far has it travelled in total?

The equation used here is speed = distance / time (s=d/t). Firstly the 30 ms^-1. Rearrange the equation to find distance (st=d). 5ms^-1 x 10s = 50m. The second stint is 6ms^-1 x 5s = 30m. This makes the tota...
MP
Answered by Marcus P. • Physics tutor
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A mass of 2kg is dropped from rest at a height of 10m. i) What is the initial GPE of the mass? ii) What is the final velocity of the mass when it hits the ground?

Part i Gravitational Potential Energy (GPE) = mass x gravitational acceleration constant x heightGPE = 2 x 9.81 x 10 = 196.2J Part ii Conservation of energy states that the sum of the GPE and KE at the intia...
ZS
Answered by Zaakir S. • Physics tutor
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Why is the sky blue?

The Earth's atmosphere scatters incoming light from the sun. This incoming light is made up of lots of different colours. Each colour of light has a different wavelength and because of this, different colour...
HS
Answered by Hector S. • Physics tutor
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Explain why gas bubbles rise faster through magma as they start to expand. (3)

Any object in a liquid/substance will experience a force called upthrust. This force is not dependent on the weight of the object, rather the amount of volume it takes up within the substance. When the objec...
GR
Answered by Gabrielle R. • Physics tutor
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