A proton enters a region of the magnetic field B with its velocity always perpendicular to the field so that it travels in a circular path with an angular speed of 2.4×104 rad/s. What is the value of B?  [Mass of proton=1.67× 10–27 kg, e= 1.6× 10–19 C]

A glass is half full of water (n=1.33), with a layer of vegetable oil (n=1.47) floating on top. A ray of light traveling downward through the oil is incident on the water at an angle of 61.4o. What happens with the ray of light? 

The length of the sliding rod is 20 cm and its speed is 3.0 m/s. If the total resistance of the loop is 0.05

A 250-turn solenoid carries a current of 5.0 A. The length of the solenoid is 14 cm. What is the magnetic field inside the solenoid?

Two mirrors are arranged as shown in the drawing (left, below).  Light is incident from the right on the first mirror at an angle of 70°.  The light reflects toward the second mirror and is reflected at angle θ.  Determine the angle θ.

A small bird of mass m is sitting on a perch of mass 7 g, which is supported by a magnetic force. The perch is 10 cm long and contains a wire carrying a current of 2.0 A. The perch is oriented at right angles to a uniform magnetic field of 0.9 T that is strong enough to support the perch and the bird. What is the mass of the bird?

A juicer has a rectangular coil of dimension [W] m by [L] m.  The coil is oriented such that its surface makes an angle of 30 degrees with the electric field.  The strength of the field is [E] N/C. Find the electric flux in N.m2/C passing through the coil. [Round off to the whole number]

Three equal point charges of -1.2 

The electric field at a point 2.0 cm from a small charged object has a strength of E=160,000 N/C and is directed away from the charge. What is the object’s charge?

A charge +5