Answer:
The magnitude of electric field is 22.58 N/C
Solution:
Given:
Force exerted in upward direction,
Charge, Q =
Now, we know by Coulomb's law,
Also,
Electric field,
Thus from these two relations, we can deduce:
F = QE
Therefore, in the question:
Here, the negative side is indicative of the Electric field acting in the opposite direction, i.e., downward direction.
The magnitude of the electric field is:
Answer:
b. Friction decreased when he went from pavement to ice and then increased two more times.
Explanation:
Frictional force depends on the normal force of the surface and a friction coefficient.
Since we're talking about the same car, the value of will remain constant whereas μ will represent the change in the frictional coefficient of the surface. Now we consider the different surfaces, cars will slide in an icy road which means that the frictional coefficient is smaller than the pavement.
After Joshua returns to the pavement road, the resulting frictional force increases and will do so one more time when he reaches the gravel road. Gravel roads have greater frictional coefficients than pavement roads which means the frictional force will increase a second time.
