Answer:
v = 15.8 m/s
Explanation:
Let's analyze the situation a little, we have a compressed spring so it has an elastic energy that will become part kinetic energy and a potential part for the man to get out of the barrel, in addition there is a friction force that they perform work against the movement. So the variation of mechanical energy is equal to the work of the fictional force
= ΔEm = -Em₀
Let's write the mechanical energy at each point
Initial
Em₀ = Ke = ½ k x²
Final
= K + U = ½ m v² + mg y
Let's use Hooke's law to find compression
F = - k x
x = -F / k
x = 4400/1100
x = - 4 m
Let's write the energy equation
fr d = ½ m v² + mgy - ½ k x²
Let's clear the speed
v² = (fr d + ½ kx² - mg y) 2 / m
v² = (40 4.00 + ½ 1100 4² - 60.0 9.8 2.50) 2/60.0
v² = (160 + 8800 - 1470) / 30
v = √ (229.66)
v = 15.8 m/s
Answer: 34.4 sec
Explanation: Assuming that the desacceleration was constant, we have a = -1.5m/s²
vi = 186 km/h → 51.6 m/s
vf = 0 (because it stopped)
Vf = Vi + at
0 = 51.6 - 1.5t
1.5t = 51.6
t = 34.4 s
Answer:
v₀ₓ = 14.34 m / s
Explanation:
We can solve this problem using the projectile launch equations.
Let's look for the time it takes to descend to the height of the cave
y = t - ½ g t²
As it rises horizontally the initial vertical speed is zero
y = 0 - ½ gt²
t = √2 y / g
t = √2 7.3 / 9-8
t = 1.22 s
This is the same time to cross the ravine
x = v₀ₓ t
v₀ₓ = x / t
v₀ₓ = 17.5 / 1.22
v₀ₓ = 14.34 m / s
This is the minimum speed.
Answer:
They are equal
Explanation:
angle of incidence = angle of reflection