Answer:
17.64 km/h
Explanation:
mass of car, m = 1000 kg
Kinetic energy of car, K = 1.2 x 10^4 J
Let the speed of car is v.
Use the formula for kinetic energy.

By substituting the values

v = 4.9 m/s
Now convert metre per second into km / h
We know that
1 km = 1000 m
1 h = 3600 second
So, 
v = 17.64 km/h
Thus, the reading of speedometer is 17.64 km/h.
Answer:
0.050 m
Explanation:
The strength of the magnetic field produced by a current-carrying wire is given by

where
is the vacuum permeability
I is the current in the wire
r is the distance from the wire
And the magnetic field around the wire forms concentric circles, and it is tangential to the circles.
In this problem, we have:
(current in the wire)
(strength of magnetic field)
Solving for r, we find the distance from the wire:

This is for the reason that individuals are not continually taking a gander at precisely the same, and on the grounds that individuals' psyches of ten work distinctively and process data in marginally extraordinary ways getting diverse understandings of similar information.
Answer: |F| = 1.28 x 10⁵ N
Explanation:
an impulse results in a change of momentum
FΔt = mΔv
F = m(vf - vi)/t
F = 2000(0 - 32) / 0.5
F = -128,000
|F| = 1.28 x 10⁵ N