Answer:
a.
, 
Explanation:
From the information given;
Using the work-energy theorem
ΔKE = W = 
K = 
∴

Since
and r_1 = 4, and r_2 = 2 (from the missing diagram which is attached below)
Then;


Answer:
F = 24 N
Explanation:
In this exercise we have a bar l = 100 m with a center of gravity x = 4 m, which force is needed to lift it from the other end
Let's use the rotational equilibrium relationship, where we consider the counterclockwise rotations as positive and fix the reference system at the point closest to the center of gravity
∑ τ = 0
F l -x W = 0
F = 
let's calculate
F =
4/100 600
F = 24 N
Answer:
Distance covered to top of the hill was : 1.755 km
Explanation:
Initial velocity = 35 km/hr
Acceleration = 2.0 km/hr²
Time taken to accelerate = 3 minutes = 3/60 hours = 1/20 hours
Formula for acceleration : a = Δv /t
v-u/t ---where u is initial velocity , v is final velocity and t is time taken for acceleration
v- 35 / 0.05 = 2
v = 35.10 km/h
Formula for distance is product of speed and time
Distance covered = 35.10 * 0.05 = 1.755 km
Answer:
D is the answer
Explanation:
D is the most highest one so
the answer is D