In 1780, in what is now referred to as \"Brady\'s Leap\", Captain Sam Brady of t
ID: 1525832 • Letter: I
Question
In 1780, in what is now referred to as "Brady's Leap", Captain Sam Brady of the U.S. Continental Army escaped certain death from his enemies by running over the edge of the cliff above Ohio's Cuyahoga river in(Figure 1), which is covered of that spot to a gorge. He landed safely on the far side of the river. It was reported that the leapt 22 ft (TildeTilde 6.7 m) across while falling 20 ft (TildeTilde 6.1 m) Part A what is the minimum speed with held need to run of the edge of the cliff to make if safely to the far side of the river? Express your answer no two significant figures and includes in appropriate units. V = __5.2___ __m/s____ Part B The world-record time for the 100 m dash is approximately 10 s. Given this, is reasonable to expect Bradly to be able to run fast enough to leap? No, the obtained speed is almost equal to the world-record. yes, the obtained speed is almost equal to the world-record. No, the obtained speed is greater than to the world-record. yes, the obtained speed is less than the world-record.Explanation / Answer
here,
height , h = 6.1 m
let the time taken be t
h = 0 + 0.5 * g * t^2
6.1 = 0 + 0.5 * 9.8 * t^2
t = 1.12 s
x = 6.7 m
the minimum speed , umin = x/t
umin = 6.7 /1.12 = 6 m/s
a)
the minimum speed is 6 m/s
b)
world record speed , v = 100 /10 = 10 m/s
as v > umin
so, it is reasonable
as the obtained speed is less than the world record