Explanation:
study of social sciencake us an effcient citizen of a democracy ,and it also help us to solve the practical problem in our daily life.
Soaking up spilled milk with a paper towel
While travelling along a highway a drivers velocity is 9 m/s. In 12 seconds, the car has gone for 108 m.
<u>Explanation:</u>
The car travelling along the highway has a uniform velocity of 9 m/s. therefore to calculate the distance travelled by the car with the uniform velocity in 12 seconds, simple formula of velocity is to be employed.
Thereby, as we know that
The displacement is along the highway with uniform motion, therefore, distance=displacement
Given that,
Velocity = 9 m/s
Time = 12 s
Putting the values in the formula, we get,
Therefore, the car travels for 108 m in the 12 seconds while travelling along highway with 9 m/s of velocity.
Answer:
155.5 rev/min
Explanation:
First, we will calculate the initial moment of inertia I_o. We will consider the ice skater as a rod rotating around its axis. Then, we calculate the final moment of inertia I_f. In this occasion we consider the arms as a rod of length L that is horizontally positioned, L so that the length of an arm is L/2. We will call M_1 the mass that remains close to the rotation axis (90 percent) and M_2 the mass located at the arms (10 percent). Finally, we write the equation for the conservation of angular momentum and we solve for ω_f.
I_o=MR^2/2
=(45)(0.15)^2/2
=0.5 kgm^2
M_1=(0.9)(45)
=40.5 kg
M_2=(0.1)(45)
=4.5 kg
I_f=M_1*R^2/2+M_2*L^2/12
=1.1 kg m^2
I_f*ω_f=I_o*ω_o
ω_f = I_o*ω_o/ I_f
=155.5 rev/min
