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.
Resistance = (voltage) / (current)
Resistance = (6.0 v) / (2.0 A)
Resistance = 3.0 ohms
Answer:
539 kPa
Explanation:
Pressure equals density times acceleration of gravity times depth.
P = ρgh
Water has a density of 1000 kg/m³, and acceleration of gravity is 9.8 m/s².
P = (1000 kg/m³) (9.8 m/s²) (55.0 m)
P = 539,000 Pa
P = 539 kPa
Work= (force)(distance)
178= m(9.81)x0.5
178=m(4.905)
178/4.905=m
His mass is 36.3 kg
Answer:
2.5
Explanation:
The capacitance of a parallel-plate capacitor filled with dielectric is given by

where
k is the dielectric constant
is the capacitance of the capacitor without dielectric
In this problem,
is the capacitance of the capacitor in air
is the capacitance with the dielectric inserted
Solving the equation for k, we find
