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If a ball is thrown on the Moon, the projectile would have a greater range than if it were to have been thrown on Earth. Why is this the case?

The Moon has a lower gravitaional field strength than the Earth, and it does not have an atmosphere. The lower gravitational field strength means that there is lower acceleration, which results in an incr...

Answered by Tutor65616 D. • Physics tutor

10457 Views

What's the difference between weight and mass and how do I find one from the other?

This is often confusing because in everyday life people might say "how much do you weigh?" to which you might say "60kg", 60 kg is actually your mass and when we talk about weig...

Answered by Jack B. • Physics tutor

2196 Views

Why is 0°C ice more effective at cooling a drink than 0°C water of the same mass?

When ice (or ice cold water) is added to a drink, the two substances move towards thermal equilibrium (the point where there is no net energy transfer between the two substances, and they have the same te...

Answered by Lily W. • Physics tutor

16709 Views

A 6.0W bulb is connected to a source of 480J of energy. Assuming the system is 100% efficient, and the bulb runs at full power, how long can it stay lit?

Bulb power = 6.0W - Energy provided = 480J - Use equation P = E / t (Power = energy/time) where power is in watts, energy is in joules, and time is in seconds - Rearrange the equation to give t = E ...

Answered by Lily W. • Physics tutor

3155 Views

If a bulb has a current of 20mA and voltage of 5V, and the current cost of electricity is £3 for a kW/hour. How much money would you spend to power the bulb for 8 hours? Are these good estimates for the current, voltage and cost of electricity?

Well we know that the power of the bulb is given by P = IV. Therefore the power = (20 x 10^-3 Coulomb per second) * (5 Joules per Coulomb) = 100 x 10^-3 Joules per second = 0.1 W.

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Answered by Anuradha V. • Physics tutor

1632 Views