Answer:
7.5 m/s²
Explanation:
Given:
v₀ = 0 m/s
v = 30 m/s
t = 4 s
Find: a
v = at + v₀
(30 m/s) = a (4 s) + (0 m/s)
a = 7.5 m/s²
Answer:
Dear user,
Answer to your query is provided below
Acceleration is zero because of no change in velocity.
Explanation:
Remember that velocity is a vector quantity and a vector can change in 3 ways
•Magnitude only
•Direction only
•Both magnitude and direction.
Now the magnitude of velocity (speed) can stay constant while the direction is changing. This is the case in circular motion.
In the question above, it is mentioned that the girl is moving along a straight road. Therefore no change in direction of velocity.
Here in this case we can use work energy theorem
As per work energy theorem
Work done by all forces = Change in kinetic Energy of the object
Total kinetic energy of the solid sphere is ZERO initially as it is given at rest.
Final total kinetic energy is sum of rotational kinetic energy and translational kinetic energy

also we know that


Now kinetic energy is given by





Now by work energy theorem
Work done = 10500 - 0 = 10500 J
So in the above case work done on sphere is 10500 J
Answer:
mph
Explanation:
= Speed of bird in still air
= Speed of wind = 44 mph
Consider the motion of the bird with the wind
= distance traveled with the wind = 9292 mi
= time taken to travel the distance with wind
Time taken to travel the distance with wind is given as

eq-1
Consider the motion of the bird with the wind
= distance traveled against the wind = 6060 mi
= time taken to travel the distance against wind
Time taken to travel the distance against wind is given as

eq-2
As per the question,
Time taken with the wind = Time taken against the wind





mph
When an object is dropped, tossed, or kicked, as long as it is not laying on the ground, it accelerates downward, because of the force of gravity acting on it.