Answer:

Explanation:
Given that
x= 150 ft

y= 14 ft
From the diagram

When ,x= 150 ft and y= 14 ft


z=150.74 ft

By differentiating with respect to time t


Here x is constant that is why


Now by putting the values in the above equation we get



Therefore the distance between balloon and observer increasing with 0.65 ft/s.
The angular speed can be solve using the formula:
w = v / r
where w is the angular speed
v is the linear velocity
r is the radius of the object
w = ( 5 m / s ) / ( 5 cm ) ( 1 m / 100 cm )
w = 100 per second
When force is applied on an object the object will not slide
So here object will remain in equilibrium after applying the force
So in this case the condition of equilibrium is maintained due to friction force that is applied on the object.
So here for equilibrium be can say

also we know that

we are given that
( applied force on the box)


So here this friction force on the cart is known as static friction

Answer: Yes it possible for a system to have negative potential energy, since the choice of the zero of potential energy is arbitrary.
Explanation:
Potential energy is defined as the energy present in an object due to its position.
Mathematically, P.E = mgh
A potential energy can be negative also. This is because zero potential energy is arbitrary. For example, at the top of a building the choice of potential energy can be zero.
Therefore, the potential energy below the building will be negative.