A student looks at a 2.1m tall classmate located 3.05m from a large lens in the classroom, which has a focal length of 2.2m. How far from the lens will the image be located?

A-4.60 μc charge is moving at a constant speed of 6.80×105 m/s in the +x−direction relative to a reference frame. at the instant when the point charge is at the origin, what is the magnetic-field vector it produces at the following points.

The percent efficiency of a machine can never be 100% (or greater), because in the real world some energy is always converted into a. heat b. work c. input force d. output force

What is the electric force acting between two charges of -0.0045 c and -0.0025 c that are 0.0060 m apart? use fe=kq1q2/r^2 and k = 9.00 x 10^9 n*m^2/c^2 a. 1.7 x 10^7 n b. -1.7 x 10^7 n c. -2.8 x 10^9 n d. 2.8 x 10^9 n