The ball is going Zero miles right before the player kicks it.
Answer:
R' = R/2
Therefore, the new resistance of the wire is twice the value of the initial resistance.
Explanation:
Consider a wire with:
Resistance = R
Length = L
Area = A = πr²
where, r = radius
ρ = resistivity
Then:
R = ρL/A
R = ρL/πr² --------------- equation 1
Now, the new wire has:
Resistance = R'
Resistivity = ρ
Length = L' = 2 L
Radius = r' = 2r
Area = πr'² = π(2r)² = 4πr²
Therefore,
R' = ρL'/πr'²
R' = ρ(2 L)/4πr²
R' = (1/2)(ρL/πr²)
using equation 1:
<u>R' = R/2</u>
<u>Therefore, the new resistance of the wire is twice the value of the initial resistance.</u>
Answer:
22.3 work is left to be done
2.4 work are done
Answer:
132.9 cm
Explanation:
Data provided in the question:
Radius of the basll = 76 cm = 0.76 m
Side of the box = 200 cm = 2 m
Density of the ball and cube are equal
let the density be 'D'
Now,
Mass of ball, M = Volume × Density
=
× D
=
× D
= 1.838D
Mass of cube, m = L³ × D
= 2³ × D
= 8D
Thus,
center of mass, y = [ My₁ + my₂ ] ÷ [M + m]
here,
y₁ = center of mass of ball with respect to floor
as the center mass of sphere lies at the center of the sphere
= Length of cube + radius of sphere
= 2 + 0.76
= 2.76 m
y₂ = Center of mass of cube =
= 1 m
Thus,
y = [ ( 1.838D × 2.76 ) + (8D × 1 ) ] ÷ [1.838D + 8D]
= 13.07288D ÷ 9.838D
= 1.329 m
or
= 132.9 cm