Answer:
The minimum speed required is 5.7395km/s.
Explanation:
To escape earth, the kinetic energy of the asteroid must be greater or equal to its gravitational potential energy:

or

where
is the mass of the asteroid,
is its distance form earth's center,
is the mass of the earth, and
is the gravitational constant.
Solving for
we get:

putting in numerical values gives


in kilometers this is

Hence, the minimum speed required is 5.7395km/s.
Black surfaces is you'r answer. or dark mater. ya those are you'r answer.
Answer:
Momentum of block B after collision =
Explanation:
Given
Before collision:
Momentum of block A =
= 
Momentum of block B =
= 
After collision:
Momentum of block A =
= 
Applying law of conservation of momentum to find momentum of block B after collision
.

Plugging in the given values and simplifying.


Adding 200 to both sides.


∴ 
Momentum of block B after collision =
Answer:
A) 31 kJ
B) 1.92 KJ
C) 40 , 2.48
Explanation:
weight of person ( m ) = 79 kg
height of jump ( h ) = 0.510 m
Compression of joint material ( d ) = 1.30 cm ≈ 0.013 m
A) calculate the force
Fd = mgh
F = mgh / d
W = mg
F(net) = W + F = mg ( 1 + 
= 79 * 9.81 ( 1 + (0.51 / 0.013) )
= 774.99 ( 40.231 ) ≈ 31 KJ
B) calculate the force when the stopping distance = 0.345 m
d = 0.345 m
Fd = mgh hence F = mgh / d
F(net) = W + F = mg ( 1 + 
= 79 * 9.81 ( 1 + (0.51 / 0.345) )
= 774.99 ( 2.478 ) = 1.92 KJ
C) Ratio of force in part a with weight of person
= 31000 / ( 79 * 9.81 ) = 31000 / 774.99 = 40
Ratio of force in part b with weight of person
= 1920 / 774.99 = 2.48
Answer:
a. chemical contamination of streams ans rivers
d. adaptation