Answer:
Answer B
Explanation:
An increase in resistance makes it harder for the electric current to pass through
Answer:
α = 3×10^-5 K^-1
Explanation:
let ΔL be the change in length of the bar of metal, ΔT be the change in temperature, L be the original length of the metal bar and let α be the coefficient of linear expansion.
then, the coefficient of linear expansion is given by:
α = ΔL/(ΔT×L)
= (0.3×10^-3)/(100)(100×10^-3)
= 3×10^-5 K^-1
Therefore, the coefficient of linear expansion is 3×10^-5 K^-1
Answer: 6.36
Explanation:
Given
Radius of grindstone, r = 4 m
Initial angular speed of grindstone, w(i) = 8 rad/s
Final angular speed of the grindstone, w(f) = 12 rad/s
Time used, t = 4 s
Angular acceleration of the grinder,
α = Δw / t
α = w(f) - w(i) / t
α = (12 - 8) / 4
α = 4/4 = 1 rad/s²
Number of complete revolution in 4s =
Δθ = w(i).t + 1/2.α.t²
Δθ = 8 * 4 + 1/2 * 1 * 4²
Δθ = 32 + 1/2 * 16
Δθ = 32 + 8
Δθ = 40 rad/s
40 rad/s = 40/2π rpm = 6.36 rpm
Therefore, the grindstone does 6.36 revolutions during the 4 s interval
Answer:
it b
Explanation:
bc A water droplet falling in the atmosphere is spherical
The path the bowling ball would most closely follow after leaving the airplane is horizontal direction.
<h3>
Path of the bowling ball</h3>
Based on the law of inertia, which is the reluctance of an object to stop moving once in motion or start moving when it is at rest.
The bowling ball will maintain the path of the airline in the first few seconds of fall, after which it will change its path to vertical direction.
Thus, the path the bowling ball would most closely follow after leaving the airplane is horizontal direction.
Learn more about horizontal direction here: brainly.com/question/2534565
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