A house brick of dimensions 21.0 cm x 10.0 cm x 7.00 cm. The brick is held under water with its largest surfaces horizontal. The density of water is 1000 kg/m3.

(a) Calculate the difference in pressure between the top and the bottom surfaces of the brick.

pressure difference =
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What happens to the light rays when they hit the specimen?

What efficiency of a car's engine when heat input is 200,000 joules and waste heat is 150,000 joules? a. 75% b. 35% c. 25% d. 85%

Afaulty model rocket moves in the xy-plane (the positive y direction is vertically upward). the rocket's acceleration has components ax(t) = ? t2 and ay(t) = ? ? ? t, where ? = 2.50 m/s4 , ? = 9.00 m/s2 , and ? = 1.40 m/s3 . at t = 0 the rocket is at the origin and has velocity ~v0 = v0x ? i + v0y ? j with v0x = 1.00 m/s and v0y = 7.00 m/s. (a) calculate the velocity and position vectors as functions of time. (b) what is the maximum height reached by the rocket? (c) sketch the path of the rocket. (d) what is the horizontal displacement of the rocket when it returns to y = 0?