since child is moving along with the wagon and we need to find the acceleration of child inside that wagon then in this case the system of interest must be child + wagon
System of interest will be the system that is used to find the force or acceleration using Newton's law
Here we have to assume that system on which if we will calculate the forces then the net value of force on that system will help to calculate the unknown quantities
So here our system will be boy + wagon
Question 1: C Question 2: B, Hope this Helps!
Answer:
The gravitational force is definitely acting downwards towards the ground and this is equal to the weight of the skydiver.
the acceleration a = 7.8 m/s²
Explanation:
Given that :
the mass of the skydiver = 60 kg
Velocity = 50 m/s
Thus; gravitational force is definitely acting downwards towards the ground and this is equal to the weight of the skydiver.
Also; the air resistance is acting upward and the resultant of both forces = mass×acceleration
So;
mg-R = ma
60(9.8) - 120 = 60(a)
588 -120 = 60a
468 = 60a
a = 
a = 7.8 m/s²
Hence, the acceleration a = 7.8 m/s²
The net force acting on the car is
3 × 10^3
Newtons.
Force is defined as the product of the mass of the body and its aaceleration,
⇒ F = ma
Substituting the above given values we get,
F =(1500kg) (2.0 m/s^2) = 3000N = 3 × 10^3N .
Answer:
It keeps our body hydrated.
Explanation: