Answer:
Efficiency = 80%
Explanation:
Given the following data;
Work output = 240 N
Work Input = 300 N
To find the mechanical efficiency of a machine;
Substituting into the equation, we have;
Efficiency = 80%
Therefore, the mechanical efficiency of the machine is 80 percent.
Given :
The ball of a ballpoint pen is 0.5 mm in diameter and has an ASTM grain size of 12.
To Find :
How many grains are there in the ball?
Solution :
Volume of ball of the ballpoint is :
Now, grain size of 12 has about 520000 grains/mm³.
Therefore, number of grains are :
Answer:
i. + 22.5 m ii. 4.0 m
Explanation:
i. Image distance
Using the lens formula
1/u + 1/v = 1/f where f = focal length = + 18.0 m, u = object distance = distance of shark away from lens = + 90.0 m and v = image distance from lens = unknown
So, we find v
1/v = 1/f - 1/u
= 1/+18 - 1/+90
= (5 - 1)/90
= 4/90
v = 90/4
= + 22.5 m
So the image is real and formed 22.5 m away on the other side of the lens.
ii Length of Shark
Using the magnification formula, m = image height/object height = image distance/object distance. image height = 1.0 m where object height = length of shark.
m = image distance/object distance
= v/u
= +22.5/+90
= 0.25
0.25 = image height/object height
So,
object height = image height/0.25
= 1.0 m/0.25
= 4.0 m
So, the length of the shark is 4.0 m
Answer: The Senate provides advice and consent on presidential nominations.
