Answer:
The angular speed after 6s is .
Explanation:
The equation
relates the moment of inertia of a rigid body, and its angular acceleration , with the force applied at a distance from the axis of rotation.
In our case, the force applied is , at a distance , to a ring with the moment of inertia of ; therefore, the angular acceleration is
Therefore, the angular speed which is
after 6 seconds is
Answer:
Balanced forces: When a number of forces acting on a body do not cause any change in its state of rest or of uniform motion along a straight line then the forces are said to be balanced forces. In other words, a body is said to be underbalanced forced when the resulting force acting on the body is zero.
The balanced forces:
⋅ Cannot set any stationary body into motion.
⋅ May change the shape and size of soft objects.
⋅ Cannot change the speed/velocity of a moving body.
Unbalanced forces:
When the resultant of all the forces acting on a body is not zero, then forces are called unbalanced forces.
Example:
⋅ Game of tug of war: When the forces exerted by both the teams are equal, then the rope does not move. But, if the force applied by team A is greater than team B, then the rope, as well as members of the weaker team, i.e., B, will be pulled towards A. The unbalanced force can (a) Set a stationary body in motion.
⋅ Set a moving body at rest.
⋅ Change the direction of motion.
Explanation:
give me an one thanks please
Answer:
1. the pencil would have the momentum and would keep going until it hits the windshield. 2. when the car suddenly accelerates, the pencil would be inert and it would move toward the back of the car until a constant speed from the car is reached.
Answer:
a. 16 s b. -1.866 kJ
Explanation:
a. Since the initial rotational speed ω₀= 3313 rev/min = 3313/60 × 2π rad/s = 346.94 rad/s. Its rotational speed becomes ω₁ = 0.75ω₀ in time t = 4 s.
We find it rotational acceleration using α = (ω₁ - ω₀)/t = (0.75ω₀ - ω₀)/t = ω₀(0.75 - 1)/t = -0.25ω₀/t = (-0.25 × 346.94 rad/s)/4 s = -21.68 rad/s².
Since the turntable stops at ω = 0, the time it takes to stop is gotten from
ω = ω₀ + αt and t = (ω - ω₀)/α = (0 - 346.94 rad/s)/-21.68 rad/s² = (-346.94/-21.68) s = 16 s.
So it takes the turntable 16 s to stop.
b. The workdone by the turntable to stop W equals its rotational kinetic energy change.
So, W = 1/2Iω² - 1/2Iω₀² = 1/2 × 0.031 kgm² × 0² - 1/2 × 0.031 kgm² × (346.94 rad/s)² = 0 - 1865.7 J = -1865.7 J = -1.8657 kJ ≅ -1.866 kJ
The object will come to a halt.
Resultant force at start:17-10=7 to the left
When additional force is added to the right,it balances the forces acting in the object.
7N to the right and 7N to the left suggests that the object will come to a halt as it is in equilibrium.