12. What applied horizontal force will accelerate a 200-kg crate at 1 m/s2 across a factory floor against a friction force half its weight?
A) 600 N
B) 1600 N
C) 1200 N
D) 2400 N

The horizontal blue line through the middle of the lens is called the optical axis. as the lamp is moved above or below the axis, keeping the horizontal distance to the center of the lens constant, how does the horizontal distance from the lens to the image change?

The two most prominent wavelengths in the light emitted by a hydrogen discharge lamp are 656(red) and 486 (blue). light from a hydrogen lamp illuminates a diffraction grating with 500 lines per mm, and the light is observed on a screen 1.50 behind the grating. what is the distance between the first-order red and blue fringes?

How do cracks affect the rate of weathering?