The transfer of heat through flowing material is convection
Resistance of a wire is directly proportional to its length and inversely proportional to the square of its radius.
Thus, if the length is doubled, and the radius is halved:
R₂ = 2R₁/(1/2)²
R₂ = 8R₁
Therefore the resistance increases eight times.
Answer:
See explanation
Explanation:
1) There are two main types of waves;
Mechanical waves and electromagnetic waves.
Mechanical waves usually require a medium for propagation, e.g sound, waves on a spiral spring, etc
Electromagnetic waves do not require a medium for propagation e.g microwaves, x-rays etc
2) The phenomenon is known as refraction. Refraction occurs at the boundary between two media because of the change in the speed of a wave as it moves from one medium to another.
Answer:
VR=2
Explanation:
driven=60
driving=30
but VR=driven/driving
VR=60/30
VR=2
hence the velocity ratio VR is 2
