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A coal fire is burning in the bottom of a furnace, with a chimney above it. Air moves into the furnace from an opening at the bottom and up the chimney. Describe how the process of convection causes this air movement.

The air is heated by the coal fire. This causes the air to expand as the molecules move further apart. As a result the air becomes less dense. The less dense air rises. The cooler air from outside the chimne...
JB
Answered by James B. • Physics tutor
7854 Views

A kettle requires 2400 Coulombs of charge to pass through its heating element, with a resistance of 6 Ohms, in a time of 200 seconds in order to boil the water inside it. Calculate the current flowing and the power of the kettle.

I=Q/t=2400/200=12AP=I V=I^2 R=12^2*6=864W Of course, when discussing the answer with a student I would verbally explain each step in detail and add more drawings to my workings. Unfortunately, I cannot do th...
SL
Answered by Sam L. • Physics tutor
7125 Views

A drone is hovering at a constant height above the ground. The mass of the drone is 7 kg. The mass of the package is 3 kg. Calculate the upward force of the Drone.

To answer this Question we will use the equation derived from Newtons second law of motion, F=ma or in this case W=mg as it is the mass of the object being accelerated by gracity, giving us it's weight The a...
FT
Answered by Finn T. • Physics tutor
4569 Views

A cyclist travels along a straight flat road. Describe the condition required for the cyclist to continue traveling along the road at a constant speed. How does this condition change if the cyclist travels up a slope?

On the flat straight road, the cyclist will travel at a constant speed if the work done by the cyclist is equal to the sum of the energy lost to air resistance by the cyclist and the frictional losses within...
HM
Answered by Hallam M. • Physics tutor
7301 Views

How do stars form?

A star is formed from a nebulae, which is a cloud of dust and gas. The dust and gas particles are drawn together by the gravitational attraction between them. As the nebulae contracts, the dust and gas parti...
SS
Answered by Stephen S. • Physics tutor
2747 Views