Answer:
Turn the heater on
Explanation:
There are two main forces involved in a balloon flight
The downward force is the total weight of the balloon: the air it contains, the gas bag, the basket, the passengers, etc.
The upward force is the weight of the of the air the balloon displaces.
During level flight
,
buoyant force = weight of displaced air - total weight of balloon
If you increase the temperature of the air in the bag, the air molecules spread out and leave through the bottom of the bag.
The balloon still has the same volume, so the weight of displaced outside air stays the same.
However, the balloon has lost some hot inside air, so its total weight decreases.
The upward force is greater than the downward force, so the balloon rises.
Answer:
13.5 m
Explanation:
M = Mass of cart = 500 kg
m = Ann's mass = 50 kg
= Velocity of Ann relative to cart = 5 m/s
= Velocity of Cart relative to Ann
As the linear momentum of the system is conserved

Time taken to reach the right end by Ann

Distance the cart will move in the 3 seconds

The negative sign indicates opposite direction
Movement of Ann will be the sum of the distances

The net movement of Ann is 13.5 m
Answer:
The linear velocity is 
Explanation:
According to the law of conservation of energy
The potential energy possessed by the hoop at the top of the inclined plane is converted to the kinetic energy at the foot of the inclined plane
The kinetic energy can be mathematically represented as

Where
is the moment of inertia possessed by the hoop which is mathematically represented as
Here R is the radius of the hoop
is the angular velocity which the hoop has at the bottom of the lower part of the inclined plane which is mathematically represented as

Where v linear speed of the hoop's center of mass just as the hoop leaves the incline and rolls onto a horizontal surface
Now expressing the above statement mathematically


=>
=> 
=> 
=> 
Substituting values


heat conduction is cut off by vacuum.
metal cover block light thereby protecting radiation