Answer:
Answer 3: When a balloon goes up higher in the air, its size will increase. Since there's less air in the upper atmosphere, there's less stuff pushing back on the balloon, and hence the pressure is lower, which allows the balloon to expand
Answer: C
Explanation:
As the balloon rises, the gas inside the balloon expands because the atmospheric pressure surrounding the balloon drops. The atmosphere is 100 to 200 times less dense at the float altitudes than on the ground. and as the air is heated inside the balloon it causes it to rise upwards (because it is lighter than the cooler air on the outside). When the pilot needs to bring the balloon down again, he simply reduces the temperature of the air inside the balloon causing it to slowly descend.
Answer:
We are Given:
initial velocity (u) = 0m/s
final velocity (v) = 25 m/s
time (t) = 10 seconds
acceleration (a) = a m/s/s
From the first equation of motion, we know that:
v = u + at
solving for a, we get:
a = (v-u) / t
now, plugging the given values in this equation
a = (25 - 0) / 10
a = 25 / 10
a = 2.5 m/s/s
Therefore, the acceleration of the car is 2.5 m/s/s
Assuming the the car is travelling to the right (→):
The information we know:
Using one of the equations of motion:
An electric force exists between the following:
-Two negative objects
-Two positive objects
-A negative object and a positive object
a . true hardness and density are physical properties
