You will have to "put force against the object to slow it down." Momentum is the force that is keeping a object moving in a certain direction so if you would want to slow down the object you will have to put another force against the object to slow it down or stop it. For example: a person kicks a ball, the ball moving is the momentum. So, if you would want to stop the ball you would have t put something in its path to slow it down which is the decreasing of it's momentum. Therefore you would put a bump in the wall and when the ball hits the bump it slows down.
Hope this helps!
Answer:
t=18s
Explanation:
The final position of an object moving at constant speed is given by the formula 
, where 
is its initial position, v its speed and t the time elapsed.
For the cheetah we have 
, and for the gazelle 
. We want to know at which t their positions are equal, that is, 
, which means,
Where we can do:
We then substitute the values we have (the initial position of the cheetah is 0m), writing the meters in km so distance units cancel out correctly:
On the last step we just multiply by 3600 because is the number of seconds in an hour.
Answer:
D = 4 m
Explanation:
Speed of cart in air track v₁ = 0.5 m/s
Speed of cart moved when air is turned off v₂= 1 m/s
The distance travelled by the cart is d₁ = 1 m
Work done (W) = F x d
Work done is equal to the kinetic energy
F x d = 1/2mv²
velocity is directly proportional to distance
therefore,
v₁²/ v₂² = d₁ / d₂
d₂ = d₁v₂² / v₁²
= 1 m x (1 m /s)² / (0.5 m/s)²
= 4 m
