Answer:
C) 40 N/m
Explanation:
If we ASSUME that the spring is un-stretched at the zero cm position
k = F/Δx = 10/0.25 = 40 N/m
Answer:
The tension is 
Explanation:
From the question we are told that
The total mass is 
The radius is 
The density of air is 
Generally the upward force acting on the balloon is mathematically represented as

=> 
=> 
Here V is the volume of the spherical helium filled balloon which is mathematically represented as

=> 
=> 
So


Depending on the height of the building they can break due to impact on the floor.
Answer:
0.572 Hz
Explanation:
given,
length of simple pendulum, l = 0.76 m
mass of the bob, m = 365 g = 0.365 Kg
angle made from the vertical, = 12°
frequency, f = ?



f = 0.572 Hz
The frequency at which pendulum vibrates is equal to 0.572 Hz
The transfer of heat from the Sun is in the form of thermal radiation (also called infrared radiation)
The transfer of heat at the person’s feet is by thermal conduction. During the day the sand will be hot so if you step on it with bare feet there will be conduction of heat to the feet.