Answer:
<h2>40 kg</h2>
Explanation:
Find the diagram relating to the question for proper explanation of the question below.
Using the principle of moment
Sum of clockwise moments = Sum of anticlockwise moments
Moment = Force * perpendicular distance
For anti-clockwise moment:
Since the 30 kg moves in the anticlockwise direction according to the diagram
ACW moment = 30 * 1 = 30 kgm
For clockwise moment
If another child sits 0.75 m away from the pivot point on the opposite side, moment of the child in clockwise direction = M * 0.75 = 0.75M (M is the mass of the unknown child).
Equating both moments we have;
0.75M = 30
M = 30/0.75
M = 40 kg
The second child's mass is 40 kg
Answer:

Explanation:
Amplitude is 35/2=17.5
Midline= Distance from ground + Amplitude = 17.5+3= 20.5
Period is time taken to finish 6 minutes
2π/b=T
2π/b=6
b=π/3

At rest, initial speed zero
x=v(initial) t+ 1/2 at^2
-1000m=0(10) + 1/2 a 10^2
-1000m=50a
a = -20 m/s^2
Answer:
The correct answer to the question is objects have zero acceleration.
Explanation:
Before answering the question, first we have to understand dynamic equilibrium .
A body moving with uniform velocity is said to be in dynamic equilibrium if the net external forces acting on the body is zero. Hence, the body is under balanced forces.
If the external forces acting on a body is not balanced, then the body will accelerate which will destroy its equilibrium condition. Hence, the necessary and sufficient condition for a body to be in dynamic equilibrium is that the forces are balanced.
When a body is in dynamic equilibrium, the body moves with uniform velocity along a straight line unless and until it is compelled by some external unbalanced forces.
Hence, the rate of change of velocity or acceleration of the body will be zero.