Answer:
240 ft
Explanation:
t = Time taken
u = Initial velocity = 96 ft/s
v = Final velocity
s = Displacement
a = Acceleration = 12 m/s² on Mars 32 ft/s² on Earth negative due to upward direction
Mars

Earth

Differentiating the first equation with respect to time we get

Equating with zero

Differentiating the second equation with respect to time we get
Equating with zero

Applying the time taken to the above equations, we get


Difference in height = 384-144 = 240 ft
The stone will travel 240 ft higher on Mars
The speed at the sound barrier is 343 m/s
<h2>
Option 2 is the correct answer.</h2>
Explanation:
Elastic collision means kinetic energy and momentum are conserved.
Let the mass of object be m and M.
Initial velocity object 1 be u₁, object 2 be u₂
Final velocity object 1 be v₁, object 2 be v₂
Initial momentum = m x u₁ + M x u₂ = 3 x 8 + M x 0 = 24 kgm/s
Final momentum = m x v₁ + M x v₂ = 3 x v₁ + M x 6 = 3v₁ + 6M
Initial kinetic energy = 0.5 m x u₁² + 0.5 M x u₂² = 0.5 x 3 x 8² + 0.5 x M x 0² = 96 J
Final kinetic energy = 0.5 m x v₁² + 0.5 M x v₂² = 0.5 x 3 x v₁² + 0.5 x M x 6² = 1.5 v₁² + 18 M
We have
Initial momentum = Final momentum
24 = 3v₁ + 6M
v₁ + 2M = 8
v₁ = 8 - 2M
Initial kinetic energy = Final kinetic energy
96 = 1.5 v₁² + 18 M
v₁² + 12 M = 64
Substituting v₁ = 8 - 2M
(8 - 2M)² + 12 M = 64
64 - 32M + 4M² + 12 M = 64
4M² = 20 M
M = 5 kg
Option 2 is the correct answer.
Disease
Lack of natural reourses
war
asteroid
Polution.