Answer:
Power generate by elephant = 666.67 W
Explanation:
Given:
Force = 2,000 N
Change in time = 45 Seconds
Distance = 15 meter
Find:
Power generate by elephant ?
Computation:
⇒ Work Done = Force × Distance
⇒ Work Done = 2,000 × 15
⇒ Work Done = 30,000
⇒ Power = Work Done / Time taken
⇒ Power generate by elephant = 30,000 / 45 seconds
⇒ Power generate by elephant = 666.67 W
Answer: acceleration is 0.5 m/s^2
Explanation: From the question, we are given the following parameters
Time t = 20s
Initial velocity U = 0
Final velocity V = 10 m/s
Using first equation of motion,
V = U + at
Where a = acceleration
Substitute all the parameters into the formula to get acceleration a
10 = 0 + 20a
10 = 20a
Make a the subject of formula
a = 10/20 = 0.5 m/s^2
The acceleration is 0.5 m/s^2
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
Answer:
Its state is in uniformly accelerated motion
Explanation:
When an object is acted upon the force of gravity only, we said that the object is in free fall.
According to Newton's second law of motion:
where F is the net force on an object, m is its mass, a its acceleration, when the net force on an object (F) is non-zero, than the object accelerates (because a is non-zero), so the object is in accelerated motion.
In case of free fall, the rate of acceleration of the object is equal to , the acceleration due to gravity, and it is constant. So, the object is moving by uniformly accelerated motion.
So, acceleration is the change of velocity in time. If no vectors are used, one can use speed:
a = (final speed - start peed)/ time = 10/5= 1 m/s^2,
Notice that the units are m/s^2, or (m/s)/s. That is speed (m/s) per unit time (s)