A ball is thrown horizontally from top of a sky-rise building 144 ft high with a velocity of 20 ft/sec. Neglecting air resistance, find d?
回答 (3)
2017-07-15 4:42 pm
Vertical component of the motion of the ball:
displacement, s = 144 ft
initial velocity, u = 0 ft/s
acceleration, a = g = 32 ft/s²
s = ut + (1/2)at²
144 = 0 + (1/2)(32)t²
16t² = 144
t² = 9
t = 3 s
Horizontal distance travels, d
= 20 × 3 ft
= 60 ft
displacement, s = 144 ft
initial velocity, u = 0 ft/s
acceleration, a = g = 32 ft/s²
s = ut + (1/2)at²
144 = 0 + (1/2)(32)t²
16t² = 144
t² = 9
t = 3 s
Horizontal distance travels, d
= 20 × 3 ft
= 60 ft
2017-07-15 5:31 pm
falling time t = √2h/g = √144*2/32 = 12/4 = 3.00 sec
horizontal distance x = Vo*t = 20.00*3.00 = 60.00 feet
horizontal distance x = Vo*t = 20.00*3.00 = 60.00 feet
2017-07-15 4:30 pm
Find d? What is d supposed to represent in that problem?
收錄日期: 2021-04-18 17:22:35
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