A particle with a charge of −1.24×10−8C is moving with instantaneous velocity v→ = (4.19×104m/s)i^ + (−3.85×104m/s)j^ . What is the force exerted on this particle by a magnetic field
(a) B = (1.40T)ıˆ and
(b) B =(1.40T)kˆ ?

For general projectile motion, when the projectile is at the highest point of its trajectory, its acceleration is zero? a)the horizontal and vertical components of its velocity are zero. b) its velocity is perpendicular to the acceleration. c)the horizontal component of its velocity is zero. d)its velocity and acceleration are both zero.

In a system, when potential energy decreases, then entropy also decreases. true false

Apebble is thrown into a calm lake, ripples are formed from the center and move outward. the water particles in the lake travel in a circular pattern that moves up and down on the surface of a lake, and the energy travels a) diagonally. b) downward. c) horizontally. d) upward.