Answer:
a) a = - 0.0833 m / s², b) t = 4.4 s
Explanation:
a) this is a kinematics exercise where the acceleration is along the inclined plane
v = v₀ - a t
a = v₀ - v / t
a = 3 - 8/60
a = - 0.0833 m / s²
b) in this case the final velocity is zero
v = v₀ - a t
0 = v₀ - at
t = v₀ / a
t = 28 / 6.4
t = 4.375 s
t = 4.4 s
To determine the object which could give the greatest impact we will apply the concept of momentum. The object that has the highest momentum will be the object that will impact the strongest. Our values are
Mass of Object A

Velocity of object A

Mass of object B

Velocity of object B

The general formula for momentum is the product between mass and velocity, then

For each object we have then,


Since the momentum of object A is greater than that of object B, then object A will make you feel force upon impact.
Answer:
Stationary
20N
Explanation:
From the graph, we see that the body traveling is on a fixed position. Therefore, it is a stationary body.
The graph given is a position - time curve.
This curve depict a body changing position with given time.
Since the line of the curve is on a single position, the body is not changing position with the passage of time therefore, it is a stationary object.
B. 20N
From Newton's third law of motion we understand that "action and reaction force are equal but oppositely directed".
Since the person is exerting a force of 20N on the balance.
So, the reaction force by the balance is 20N upward.
Define heat capacity of a substance:
- The heat capacity of a substance can be defined as the amount of heat required to change its temperature by one degree.
Write the S.I unit of heat capacity:









-,-
Answer:
The time rate of change of flux is

Explanation:
Given :
Current
A
Area of plate

Plate separation
m
(A)
First find the capacitance of capacitor,

Where 

F
But 
Where 


Now differentiate above equation wrt. time,



Therefore, the time rate of change of flux is
