Physics Answers

A certain region of space bounded by an imaginary closed surface contains no charge. Is the electric field always zero everywhere on the surface? If not, under what circumstances is it zero on the surface?

The voltage across a 10 μF capacitor to charge it with 10 mC is

The air temperature and the velocity of the air have different values at different places in the earth’s atmosphere. Is the air velocity a vector field? Why or why not? Is the air temperature a vector field? Again, why or why not? 

Two identical metal objects are mounted on insulating stands. Describe how you could place charges of opposite sign but exactly equal magnitude on the two objects.

Sufficiently strong electric fields can cause atoms to become positively ionized—that is, to lose one or more electrons. Explain how this can happen. What determines how strong the field must be to make this happen?

show that unit vector normal to the surface n= ∇φ ÷ | ∇φ | . find n for the ellipsoid.

φ = a(x^2) + b(y^2) +c(z^2)

That the human heart works as a powerful and highly effective pump, as every day it receives and discharges about 7500 liters of blood, suppose that the work done (work) before is equal to the work to raise this increase of blood a height equal to its height, m ​​1.65, if you know that the density of blood is kg / m 3 1060 and acceleration m / s 9.8 Calculate the power of the heart in watts (W)

A stone is thrown straight downward with a speed of 20 m/s from the top of a tall building. If the stone strikes the ground 3 s later, how tall is the building? Assume air resistance is negligible.

Determine the location where an object with mass m0 when placed between the moon and earth experiences a gravitational force from the moon equal to a third of the gravitational force from earth. The distance from the earth to moon is 384,400 km. The ratio of mases between moon and earth is 0.0123. The radii of moon and earth are 1738.1 km and 6378.1 km, respectively.

What average force is required to push a 20.0 -kg stroller with your toddler in it for 5.0 seconds if the weight of the toddler is 15.0 kg? Suppose that you can push with a speed of 1 m/s and the stroller is initially at rest