The ballerinas takes advantage of the moment of interia by not stretching her hands out etc. and by doing so decreasing the moment of interia and therefore a smaller torque is produced to rotate at a faster rate.
Knowing the direction of a force is important because it helps someone know the motion of the object. if you use a free body diagram, then it becomes easy to see all the forces being applied to an object. if there is more force going one way, the object is accelerating in that direction. if all the forces cancel each other out, then the object is at a constant speed or is at rest.
Force is a vector quantity and denotes any interaction that change the motion of an object in a certain direction. When influence by force an object can change its velocity or
The two things that are a included when describing force are: magnitude and direction. To fully describe the force acting upon an object, you must describe both the magnitude (size or numerical value) and the direction.
Answer:
Momentum = 1.534 kgm/s
Explanation:
Using the equations of motion, we can obtain the velocity of the ball as it hits the ground.
g = 9.8 m/s²
y = 12 m
u = initial velocity = 0 m/s, since the ball was released from rest
v = final velocity befor the ball hits the ground.
v² = u² + 2ay
v² = 0 + 2×9.8×12 = 235.2
v = 15.34 m/s
The momentum at any point is given as mass × velocity at that point
Mass = 100 g = 0.1 kg, velocity = 15.34 m/s
Momentum = 0.1 × 15.34 = 1.534 kgm/s
