The Correct answer: 18
They are also known as families because they are in the same column.
The equation to be used is for the rectilinear motion at constant acceleration:
x = v₀t + 0.5at²
a = (v-v₀)/t
where
x is distance
v and v₀ is the final and initial velocity
t is time
a is acceleration
Because the acceleration is decelerating, that would be reported as -7.5 m/s². Substituting,
-7.5 = (0 - v₀)/t
v₀ = 7.5 t --> eqn 1
x = v₀t + 0.5at²
60 = (7.5t)(t) + 0.5(-7.5)(t²)
Solving for t,
t = 4s
Thus,
v₀ = 7.5 m/s² * 4s
v₀ = 30 m/s
Answer:
(a) 8.117 (b) 0.742
Explanation:
We have given distance s =40 m time t=7.5 sec
Final velocity v =2.55 m/sec
From the first equation of motion 
(negative sign because there is retrdation as the truck speed is slowing down )
So 
--------------eqn 1
From the second equation of motion 
( negative sign because there is retrdation as the truck speed is slowing down )
So 
------------------eqn 2
On solving eqn1 and eqn 2
u=8.117 m/sec and a=-0.742
Work = (force) x (distance)
If the distance is zero (the object doesn't move), then it
doesn't matter how great the force is. The work is still zero.
Answer:
Equilibrium
Explanation:
An object is in equilibrium when the vector sum of the force acting on the object is equal to zero.
A body in equilibrium is at state of rest of rest or in motion with no external force acting on it.
- The resultant of all forces acting on the body is zero.
- In this case there is no net force and the body will be at rest.
