Answer:
The correct answer is D. decimal point.
Explanation:
The question is wrong. It should be :
When converting from a smaller to a larger unit of measurement, you move the _______ to the left.
In order to convert from a smaller to a larger unit of measurement what we need to move is the decimal point to the left. Let's see an example :
We have the two following units
'''' which is grams and ''
'' which is kilograms.
We know that the grams are a smaller unit of measurement that kilograms.
We also know the relationship :
For example if we want to convert to kilograms :
What we have done is that we divided the number ''1500'' by ''1000''.
This is equal to move the decimal point three places to the left ⇒
The correct answer is D. decimal point
Given data:
* The extension of the steel wire is 0.3 mm.
* The length of the wire is 4 m.
* The area of cross section of wire is,
* The young modulus of the steel is,
Solution:
The young modulus of the steel in terms of the force and extension is,
where F is the force acting on the steel wire,, l is the original length of the wire, dl is the extension of the wire, and A is the area,
Substituting the known values,
Thus, the force which produce the extension of 0.3 mm of the steel wire is 31.5 N.
Answer:
-13,594 J
Explanation:
First of all, we have to find the acceleration of the girl+sled system. This can be found by using Newton's second law of motion:
where:
F = -96 N is the net force (the force of friction) acting on the system
m = 28.4+15.3 = 43.7 kg is the total mass of the girl and the sled
a is their acceleration
Solving for a,
The negative sign means the sled is slowing down.
Now we can find the displacement of the sled during the deceleration phase, by using the suvat equation:
where
u = 41.8 m/s is the initial velocity
t = 3.76 s is the time
is the acceleration
So,
Now we can find the work done by friction on the sled, which is given by:
where
F = -96 N is the force of friction
s = 141.6 m is the displacement of the sled+girl system
Solving,
where the negative sign means the force is opposite to the displacement.