Answer:
vf=at+v0. vf=0
-v0=at
t=-v0/a=(-27m/s)/(-8m/s^2)=3.4s
Answer:
From C to D, kinetic energy is transformed into gravitational potential energy.
i think
Answer:
The projectile's speed as it passes the satellite is 1497.8 m/s.
Explanation:
Given that,
Radius of planet 
Mass of planet 
Speed = 2000 m/s
Height = 1000 km
We need to calculate the projectile's speed as it passes the satellite
Using conservation of energy






Put the value into the formula


Hence, The projectile's speed as it passes the satellite is 1497.8 m/s.
answer:They are too close to the sun!
Explanation:Because Mercury is so close to the Sun and its gravity, it wouldn't be able to hold on to its own moon. Any moon would most likely crash into Mercury or maybe go into orbit around the Sun and eventually get pulled into it.Same with Venus!
Given :
Initial velocity , u = 0 m/s² .
To Find :
The acceleration of the cart.
Solution :
Since, acceleration is constant.
Using equation of motion :

Putting, t = 1 s and x = 4 m in above equation, we get :

Therefore, the acceleration of the cart is 8 m/s².