Answer:
The torque on the pulley, when the system is motionless is approximately 9.81 N·m
Explanation:
The given parameters are;
The mass of the object = 2 kg
The friction between the rope and the pulley = 0
The mass of the rope, = 0.5 kg
The mass of the pulley, = 0.01 kg
The radius of the pulley, r = 0.25 m
The torque on the pulley, τ = I·α = F × D
The torque on the pulley, when the system is motionless, τ = F × D
Where;
F = The force acting on the pulley rope = The weight of the mass ≈ 2 kg × 9.81 m/s² = 19.62 N
D = The diameter of the pulley = 2×r = 2 × 0.25 m = 0.5 m
Therefore;
τ = 19.62 N × 0.5 m = 9.81 N·m
The torque on the pulley, when the system is motionless, τ ≈ 9.81 N·m.
Given:
Total distance = 1000 kilometer
Total time = 5 hours
To find:
Average speed = ?
Formula used:
=
Where = average speed
s = total distance
t = total time
Solution:
Average speed of the jet is given by,
=
Where = average speed
s = total distance
t = total time
=
= 200 km/ h
Thus, average speed of the jet is 200 km/h.
Hence, Option (A) is correct.
Answer:
Relation between initial speed of bullet and height h is given as
Explanation:
As we know that system of block and bullet swings up to height h after collision
So we have
so we have
so speed of the block + bullet just after the impact is given by above equation
Now we also know that there is no force on the system of bullet + block in the direction of motion
So we can use momentum conservation
now we have