Answer:
v= 13 m/s
Explanation:
Velocity is defined as the derivative of displacement with respect to time
v= ds/dt
Known data
s(t) = 5t + 2t² : distance that the ball has rolled after t seconds
vi= 5 m/s : initial velocity
t= 2 s
Problem develoment
s(t) = 5t + 2t²
v= ds/dt= 5 + 4t : velocity of the ball in function of the time
We replace t =2 s in the equation of velocity
v= 5 + 4(2)
v= 13 m/s : velocity after 2 seconds
On a velocity - time graph, if the line crosses the x - axis it depicts that the object has started moving in the opposite direction.
Answer:
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Explanation:
It is given that,
Speed of the projectile is 0.5 v. Let h is the height above the ground. Using the first equation of motion to find it.
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Initial speed of the projectile is v and final speed is 0.5 v.
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
g is the acceleration due to gravity
Let h is the height above the ground. Using the second equation of motion as :
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
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So, the height of the projectile above the ground is
. Hence, this is the required solution.
I would say letter A to this because we need rain water for crops plants. Also we need it so that we can drink it. Its less great over sea because as it merge with the salt in the ocean it becomes less drinkable and less usable.
Colloid mixtures can be solids, liquids, or gases.
EX- Would include, butter, milk, and frog. There are actually 8 types of colloid mixtures, they are usally described by orginal state.