You get 493.41 when
you subtract 15.54 from 508.953 using the rules for significant figures.
For addition
and subtraction, look at the decimal portion (i.e., to the right of the decimal
point) of the numbers ONLY. Here is what to do:
1) Count the
number of significant figures in the decimal portion of each number in the
problem. (The digits to the left of the decimal place are not used to determine
the number of decimal places in the final answer.)
2) Add or
subtract in the normal fashion.
3) Round the
answer to the LEAST number of places in the decimal portion of any number in
the problem.
The correct answer between all the choices given is the
third choice or letter C. I am hoping that this answer has satisfied your query
and it will be able to help you in your endeavor, and if you would like, feel
free to ask another question.
Answer:
1.5 m/s²
Explanation:
For the block to move, it must first overcome the static friction.
Fs = N μs
Fs = (45 N) (0.42)
Fs = 18.9 N
This is less than the 36 N applied, so the block will move. Since the block is moving, kinetic friction takes over. To find the block's acceleration, use Newton's second law:
∑F = ma
F − N μk = ma
36 N − (45 N) (0.65) = (45 N / 9.8 m/s²) a
6.75 N = 4.59 kg a
a = 1.47 m/s²
Rounded to two significant figures, the block's acceleration is 1.5 m/s².
Usually the coefficient of static friction is greater than the coefficient of kinetic friction. You might want to double check the problem statement, just to be sure.
The chemical symbol always begins with a capital letter.
.
Find the volume of the bottom and top separately and then add them.
Cylinder volume is the area of the bottom times the height
(22/7)(5^2)•175=13750 ft^3
The volume of a sphere is
V=(4/3)(22/7)r^3
where r is the radius. Here that's also 5 since it fits on the cylinder.
Also we only want half the sphere so use
V=(2/3)(22/7)•5^3=261.9 ft^3
Which we round upto 262.
Now add the parts together
13750+262=14,012 ft^3