Answer:
The amount of potential energy that was initially stored in the spring is 88.8 J.
Explanation:
Given that,
Mass of block = 1.60 kg
Angle = 30.0°
Distance = 6.55 m
Speed = 7.50 m/s
Coefficient of kinetic friction = 0.50
We need to calculate the amount of potential energy
Using formula of conservation of energy between point A and B



Put the value into the formula


Hence, The amount of potential energy that was initially stored in the spring is 88.8 J.
Answer:
W = 1884J
Explanation:
This question is incomplete. The original question was:
<em>Consider a motor that exerts a constant torque of 25.0 N.m to a horizontal platform whose moment of inertia is 50.0kg.m^2 . Assume that the platform is initially at rest and the torque is applied for 12.0rotations . Neglect friction.
</em>
<em>
How much work W does the motor do on the platform during this process? Enter your answer in joules to four significant figures.</em>
The amount of work done by the motor is given by:


Where I = 50kg.m^2 and ωo = rad/s. We need to calculate ωf.
By using kinematics:

But we don't have the acceleration yet. So, we have to calculate it by making a sum of torque:

=> 
Now we can calculate the final velocity:

Finally, we calculate the total work:

Since the question asked to "<em>Enter your answer in joules to four significant figures.</em>":
W = 1884J
The two spheres have opposite charges.
<h3 /><h3 /><h3>What are types charge?</h3>
- A charge can be negatively charged or positively charged.
- When two charges have opposite signs, that is positive and negative signs, the two charges will attract each other.
- When the two charges have the same sign, it causes repulsion.
When a positive charge points downwards ↓ and the negative charge points upwards ↑, this causes attraction and shows that the two charges are different.
Thus, we can conclude that the two spheres have opposite charges.
Learn more about attraction and repulsion of charges here: brainly.com/question/2396080
Ans: The thin strands are called as yarns which are made from fibre. Spinning is the process of making yarn. The process where the cotton wool are drawn out and being twisted. This process brings all the fibre together to form a yarn.