Read each statement, one at a time, and form the picture in your mind.
<em>Statement #1</em> should make you feel all warm and fuzzy inside.
Statements #2, #3, and #4 should make your red flag wave on the inside, and should make you giggle on the outside when you realize how absurd each of those is.
Answer:
1. False
some metals are ferromagnetic
2.True
3. True
4. True
5. False
The strength of electromagnetic can be increased by increasing the number of wire around it
Answer:
The kinetic energy of the merry-goround after 3.62 s is 544J
Explanation:
Given :
Weight w = 745 N
Radius r = 1.45 m
Force = 56.3 N
To Find:
The kinetic energy of the merry-go round after 3.62 = ?
Solution:
Step 1: Finding the Mass of merry-go-round


m = 76.02 kg
Step 2: Finding the Moment of Inertia of solid cylinder
Moment of Inertia of solid cylinder I =
Substituting the values
Moment of Inertia of solid cylinder I
=>
=> 
=> 
Step 3: Finding the Torque applied T
Torque applied T =
Substituting the values
T = 
T = 81.635 N.m
Step 4: Finding the Angular acceleration
Angular acceleration ,
Substituting the values,


Step 4: Finding the Final angular velocity
Final angular velocity ,
Substituting the values,


Now KE (100% rotational) after 3.62s is:
KE = 
KE =
KE = 544J
A) Calling F the intensity of the horizontal force and d the displacement of the block across the floor, the work done by the horizontal force is equal to

b) The work done by the frictional force against the motion of the block is equal to:


Part of these 105.1 Joules of work becomes increase of thermal energy of the block (

), and part of it becomes increase of thermal energy of the floor (

). We already know the increase in thermal energy of the block (38.2 J), so we can find the increase in thermal energy of the floor:

c) The net work done on the block is the work done by the horizontal force F minus the work done by the frictional force (the frictional force acts against the motion, so we must take it with a negative sign):

For the work-energy theorem, the work done on the block is equal to its increase of kinetic energy:

So, we have
<span>(1) Connect one red clamp to the positive (+) battery post of the "dead" battery.(2) Connect the other red clamp to the positive (+) post of the good battery.(3) Connect one black-end clamp to the negative (-) post of the good battery.(4) Carefully connect the other black-end clamp to some large metallic part of your car's engine block. Never connect it to the negative (-) post of the "dead" battery because this causes sparking which could ignite battery gases.<span>hope this helps </span></span>