Answer: D
Explanation: :) Just took the quizz
-- During the time the ball is flying from the high roof to the low roof,
it's going to fall (100-25) = 75 meters.
How long does it take an object dropped from rest to fall 75 meters ?
Distance = (1/2) · (gravity) · (time)²
75 m = (4.9 m/s²) · (time)²
Time² = (75 m) / (4.9 m/s²)
Time² = 15.31 sec²
Time = √(15.31 sec²) = 3.91 seconds
So the ball has to cover the horizontal distance of 20 meters
in 3.91 seconds.
Distance = (speed) · (time)
20 m = (speed) · (3.91 sec)
Speed = (20 m) / (3.91 sec)
Speed = 5.11 m/s
Answer:
Explanation:
The hand throwing ball moves on a circular path having radius r = .55 m
mass of ball m = .19 kg
velocity v = 70 mph
= 70 x 1600 / 60 x 60
= 31.11 m /s
centripetal force
= mv² / r
= .19 x 31.11² / .55
= 334.34 N
Answer:
54 g
Explanation:
Mass is conserved. Mass of reactants = mass of products.
24 g + 96 g = 66 g + x
x = 54 g
