Physics Answers

A 198.4 and a 318.3-kg cart approach each other on a horizontal air track. They collide and stick together. After the collision their total kinetic energy is 1011. What is the speed after the collision?

If the work required to speed a car from 10 km/h to 20 km/h is 5.0 x 10^3 J, what would be the work required to increase its speed from 20 km/h to 30 km/h.

A circular loop of wire of radius 0.25 cm is expected to an external magnetic field that is perpendicular to the plane of the loop. For a time, the magnetic field decreases at a rate of 0.0035 T/s. What is the magnitude of the induced electromagnetic force in the loop?

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A flexible rectangular coil of wire with 150 loops is stretched in such a way that its dimension changes from 5 cm x 8 cm to 7 cm x 11 cm in 0.15 s in a magnetic field of 25T that is 30 degrees relative to the plane of the coil.

a. Calculate the induced EMF

b. How much energy in joules was dissipated in the circuit if the total resistance is 100Ω?

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A truck starts from rest and moves with a

constant acceleration of 5.0 m/s2

. Find its

speed and the distance travelled after 4.0

seconds has elapsed.

An object is projected from the ground with an initial velocity of 28.5m/s at 35⁰ above the horizontal. Find the following:

(a) horizontal and vertical components of its initial velocity,

(b) time to reach the maximum height,

(c) time of flight,

(d) maximum height,

(e) the speed at the maximum height

(f) range, and

(g) velocity upon striking the ground.

At what angle of incidence is light completely polarized after reflection from a surface of water? What is the corresponding angle of refraction? Assume that light is incident from air. The n of water=1.33.

A current of 3A flows for 50hr through a 6ohm resistor find the energy consumed by the resistor

Two electric train A and B leave the same station on parallel rail line train A start at rest with a uniform acceleration of 0.2m/s2 and attain a speed of 45km/h and maintain this speed at constant rate after ward . the train B leave the station 1 minute after train A has left and move with uniform acceleration of 0.4m/s2 to attain a maximum speed of 72 km/h. If train B maintain the speed of 72km/h determine the time it will over take train A

A ball thrown vertically upward returns to its starting point at 4s. Find its initial speed.