Answer:
4.15 m/s
Explanation:
Its given that acceleration is 0.1 m/s² with a direction opposite to the velocity. Since, the direction of acceleration is opposite to the velocity, this gives us a hint that the velocity is decreasing and so acceleration would be negative.
i.e.
acceleration = a = - 0.1 m/s²
Distance covered = S = 6m
Velocity after covering 6 meters = Final velocity = 
= 4 m/s
We need to find the initial speed, which will be the same as the magnitude of initial velocity.
Initial velocity = 
= ?
3rd equation of motion relates the acceleration, distance, final velocity and initial velocity as:
Using the known values in the formula, we get:
Thus, the initial speed of the ball was 4.15 m/s
Answer:
2677.3 N
Explanation:
v₀ = initial speed of the hand = 4.75 m/s
v = final speed of the hand = 0 m/s
m = Total mass of hand and forearm = 1.55 kg
t = time interval for hand to come to rest = 2.75 ms = 0.00275 s
F = Force applied on the leg
Using Impulse-change in momentum equation
F t = m (v - v₀)
F (0.00275) = (1.55) (0 - 4.75)
F = - 2677.3 N
magnitude of force = 2677.3 N
Explanation:
Since its accelerating, the velocity vs time graph is linear
For displacement we need initial velocity (which is zero because it starts from rest) and final velocity (which is calculatee thro acceleration formula
A= (vf - vi)/t
a= vf-0/t
1.25=vf / 7
1.25*7=vf
8.75 = vf
Now for displacement plug all the values in
X = 1/2(vf-vi)/t formula
The displacement (x) is 30.625 m
For part 3, we know new displacement that is 22m , the final and initial velocities are the same so just plug in the values for same formula above
The answer is t = 5.02
Im pretty sure all the answers are correct
Answer:
31677.2 lb
Explanation:
mass of hammer (m) = 3.7 lb
initial velocity (u) = 5.8 ft/s
final velocity (v) = 0
time (t) = 0.00068 s
acceleration due to gravity (g) 32 ft/s^{2}
force = m x ( a + g )
where
- m is the mass = 3.7 lb
- g is the acceleration due to gravity = 32 ft/s^{2}
- a is the acceleration of the hammer
from v = u + at
a = (v-u)/ t
a = (0-5.8)/0.00068 = -8529.4 ( the negative sign showa the its decelerating)
we can substitute all required values into force= m x (a+g)
force = 3.7 x (8529.4 + 32) = 31677.2 lb
You forgot to add a photo.
