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Compare and contrast elastic and inelastic collisions

An elastic collision is a collision where there is no loss of kinetic energy. Therefore, it can be said that, since KE is conserved, momentum is conserved. In other words the momentum and total kinetic en...

Answered by Matt R. • Physics tutor

12938 Views

Explain why increase in current results in higher temperature of the wire.

Current is a measure of the rate of change of charged electrons going through the wire. Therefore, when the current increases more electrons are passing through the wire in a unit time. Thus, their averag...

Answered by Braian L. • Physics tutor

1312 Views

A transformer has an input voltage of 4V, an output voltage of 8V and 50 turns on its primary coil. Assuming 100% efficiency, find the number of turns on the secondary coil.

Using Vp/Vs=Np/Ns, we can rearrange to get Ns= (VsNp)/VpSo, Ns = 8*50/4=100 turns.

Answered by Joe W. • Physics tutor

2149 Views

A projectile is launched from ground level with a speed of 25 m/s at an angle of 42° to the horizontal. What is the horizontal distance from the starting point of the projectile when it hits the ground?

Resolve the vertical velocity of the projectile (25sin42) and use v=u+at where v=-25sin42m/s, u=25sin42m/s, a=-9.8m/s/s to find t. t= (50sin42)/9.8= 3.41sResolve horizontal velocity (25cos42) and multiply...

Answered by Joe W. • Physics tutor

16258 Views

A tractor pulls a plough 2km across a field using a constant force of 8N, what is the work done by the tractor?

Work done= F x d; where d= distance object has been moved through in same direction of force and F= resultant force. F=8 N.d=2 x 1000 m.WD = 2000 x 8 = 16000 J

Answered by Lily B. • Physics tutor

2965 Views