B. because my sister said so
Answer: 1608.39 J
Explanation: Given that the
mass M = 42kg
U = 11.5m/s
V = 3.33m/s
how much work did friction do
Work done = Force × distance
Work done = Ma × distance
But acceleration a = V/t
Work done = M × V/t × d
Work done = M × V × d/t
Where d/t = velocity
Therefore,
Work done = M × U × V
Work done = 42 × 11.5 × 3.33
Work done = 1608.39 J
Answer:
The sphere's volume charge density is 2.58 μC/m³.
Explanation:
Given that,
Radius of sphere R= 8.40 cm
Electric field 
Distance r= 16.8 cm
We need to calculate the sphere's volume charge density
Using Gauss's law



Put the value into the formula



Hence, The sphere's volume charge density is 2.58 μC/m³.
Answer:
1. What was the diameter of the hailstone in inches_5.09_ and in cm___12.92___ and in feet ____0.42___?
2. What was the total volume of the hailstone in cubic inches___68.64___ and cubic feet____0.03____?
3. What was the fall velocity of this hailstone in m/s_____2.584____ and in mph___5.78_____?
Explanation:
1. If the circumference (L) of the stone is 16 inches, then from the following equation



1 inch = 2.54 cm = 0.08 ft, so 5.09 inches = 12..92 cm = 0.42 ft
2. The total volume is

3. The fall velocity is V = kd, where k = 20 if d is in cm. Let's calculate the fall velocity in cm.

2.584 m/s = 5.78 mph