It is true that a physical change occurs when a material changes shape or size, but the composition of the material does not change. The correct answer is True.
The minimum input force she'll need to lift the ball is 35 N.
Explanation:
Mechanical advantage of a single pulley is 1. As, she applies 70 N of force to lift the bowling ball, so the output force(weight of the ball) is also 70 N.
Now, adding another pulley gives a mechanical advantage of 2. We have,
M.A = (Output Force)/(Input Force)
Substituting the values we get,

= 35 N
Input force equals to 35 N needs to be applied.
Answer: The volume of an irregularly shaped object is 0.50 ml
Explanation:
To calculate the volume, we use the equation:

Density of object = 
mass of object = 3.0 g
Volume of object = ?
Putting in the values we get:


Thus the volume of an irregularly shaped object is 0.50 ml
Answer:
The movable piston
Explanation:
Work is said to be done when a distance is been covered by a force . In this case kinetic energy will be change by an equal amount into work done.
Pushing the piston with a known mass of (m) and an accelarating rate from rest of ( a) to cover a known distance of (d).The idea of work done is been achieved and can be mathematically represented by:
- Work done = Force x distance (d)
- Force = mass (m) x acceleration (a)