Answer:
basically they have too much mass in them
Explanation:
They are held tightly together by strong forces of attraction. They are held in fixed positions but they do vibrate. Because the particles don't move, solids have a definite shape and volume, and can't flow. Because the particles are already packed closely together, solids can't easily be compressed.
Correct Answers is A.
The machines gives us some mechanical advantage. This means the mechanical average makes the work output greater than the work input
Simple most example is a lever. The force applied is smaller and the output work is larger as compared to input.
Option B cannot be true, as there must be a force to get some work done.
Option C and D are inverse of what a machine is designed for. A small force can be exerted through a large distance to have a large force exerted through a small distance. Common Example of this principle is a screw opener.
The current is defined as the amount of charge transferred through a certain point in a certain time interval:
where
I is the current
Q is the charge
is the time interval
For the lightning bolt in our problem, Q=6.0 C and
, so the average current during the event is
We know average speed =total distance/time taken
So avg speed=(85+63)/(5+5)=14.8km/hr
4. E
5. D
6. F
Hope this helps
