Answer:
1 mole of H2O is 18 grams (2 g H + 16 g Oxygen)
36 / 18 = 2
So 2 moles = 2 * 6.02E23 = 12.04E23 = 1.204E24
Answer:
Accuracy is how close a measured value is to an accepted value. <u>Precision is how close measurements are to one another.</u> To make measurements, you have to evaluate both the accuracy and the precision to get a correct value.
Answer:
4 m/s²
Explanation:
When the elevator is 1 m below point of contact , compression will be 1 m.
Restoring force in the spring will be 10600 N. Friction force of 17000N will also act in upward direction . The weight of 2000 x 9.8 N will act downwards
Force in down ward direction = 2000 x 9.8
= 19600 N
Force in upward direction
= 10600 + 17000
= 27600 N
Net force in upward direction
= 27600 - 19600
= 8000 N
Acceleration in upward direction
= 8000 / 2000
= 4 m/s²
(a) This is a freefall problem in disguise - when the ball returns to its original position, it will be going at the same speed but in the opposite direction. So the ball's final velocity is the negative of its initial velocity.
Recall that
We have 
, so that
(b) The speed of the ball at the start and at the end of the roll are the same 8 m/s, so the average speed is also 8 m/s.
(c) The ball's average velocity is 0. Average velocity is given by 
, and we know that .
(d) The position of the ball 
at time 
is given by
Take the starting position to be the origin, 
. Then after 6 seconds,
so the ball is 42 m away from where it started.
We're not asked to say in which direction it's moving at this point, but just out of curiosity we can determine that too:
Since the velocity is positive, the ball is still moving up the incline.
Answer:
PE is related to the ability to do work, If an item is sitting on a shelf
it has potential energy relative to its position on the floor, However, if the object were to fall it would hit the floor with a KE equal to the PE that it had sitting on the shelf.
Sounds are caused by compressional waves in the air - when a piano key is struck or a TV is turned on, then compressional waves are produced in the surrounding air due to a disturbance. The human ear recognizes the disturbed air as due to the object that created the disturbance.
