A stone is thrown horizontally with an initial speed of 30 m/s from a bridge. Find the stone’s total speed when it enters the water 4 seconds later. (Ignore air resistance.)()
A. 30 m/s
B. 40 m/s
C. 50 m/s
D. 60 m/s
E. 70 m/s
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A speeder traveling at a constant speed of 100 km/hr passes a waiting police car that immediately starts from rest and accelerates at a constant 2.5 m/s^2. How fast will the police car be traveling wh
A. 200 km/hr
B. 210 km/hr
C. 220 km/hr
D. 190 km/hr
E. 180 km/hr
F. 230 km/hr
The unit of work, joule, is dimensionally the same as()
A. newton/second
B. newton/kilogram
C. newton-second
D. newton-meter
The acceleration of a bus is given by a(t) =α*t, where α = 1.2 m/s^3. If the bus’s velocity at time t = 1.0s is 5.0 m/s, what is its velocity at time t = 2.0 s()
A. 6.8 m/s
B. 5.6 m/s
C. 4.5 m/s
D. 7.6 m/s
E. 8 m/s
F. 5 m/s
Plane A is flying at 400 mph in the northeast direction relative to the earth. Plane B is flying at 500 mph in the north direction relative to the earth. What is the speed of Plane B as observed from
A. 900 mph
B. 600 mph
C. 357 mph
D. 100 mph
E. 650 mph
F. 450 mphG.245 mphH.136 mph