Answer: h = 3R
Explanation:
Using the law of conservation of energy,
Total energy at the beginning of the launch would be equal to total energy at any point.
kinetic energy + gravitational potential energy = constant
Initial energy of the projectile =
... (1)
where R is the radius of the Earth, M is the mass ofthe Earth, m is the mass of the projectile.
escape velocity, 
Total energy at height h above the Earth where speed of the projectile is half the escape velocity:
...(2)
(1)=(2)
⇒
⇒
⇒
⇒
⇒h = 3R
Thus, at height equal to thrice radius of Earth, the speed of the projectile would reduce to half of escape velocity.
Answer:
Option (D) is correct.
Explanation:
The balloon lands horizontally at a distance of 420 m from a point where it as released.
Velocity of air balloon along +X axis =10 m/s
velocity of ball=4 m/s along + X axis
the velocity of balloon gets added to the velocity of ball. So the resultant velocity of the balloon=10+4 = 14 m/s
time taken= 30 s
The distance traveled is given by d= v t
d= 14 (30)
d= 420 m
Thus the balloon lands horizontally at a distance of 420 m from a point where it as released.
Answer:
Solar power drives Earth's climate. Energy from the sun heats Earth's surface, warms the atmosphere, provides energy for photosynthesis, causes evaporation, drives the weather and water cycles, and powers the ocean currents. ... This circle represents the Earth and the inner-most
Answer:
260 km
65 km/hr
Explanation:
The displacement of an object is the distance moved by that object in a particular direction.
velocity = displacement / time, therefore,
Displacement = velocity * time.
Total displacement for the 4 HR trip = displacement for 2.5 hr + displacement for 1.5 hr
total displacement = (80 * 2.5) + (40 * 1.5)
Total displacement = 200 + 60
Total displacement = 260 Km
average velocity for the total trip = total displacement / total time taken
average velocity = 260 km/ 4 hr
average velocity = 65 km/hr