Answer:
C) Use a battery with more voltage.
Explanation:
The equation for the magnetic field around a coil is given by,
B = μ₀NI
where,
B = Magnetic flux density
μ₀ = permeability
N = number of turns per meter
I = Current in the wire
So when using a higher voltage battery, more current passes through the battery as resistance of the wire remains the same.
Answer:

Explanation:
The gravitational potential energy gets transformed into translational and rotational kinetic energy, so we can write
. Since
(the ball rolls without slipping) and for a solid sphere
, we have:

So our translational speed will be:

Answer:
1) 6 seconds
2) 60 m/s
Explanation:
Given:
Δy = 180 m
v₀ = 0 m/s
a = 10 m/s²
1) Find t.
Δy = v₀ t + ½ at²
180 m = (0 m/s) t + ½ (10 m/s²) t²
t = 6 s
2) Find v.
v² = v₀² + 2aΔy
v² = (0 m/s)² + 2 (10 m/s²) (180 m)
v = 60 m/s