Answer:
Zero
Explanation:
Net force can be defined as the vector sum of all the forces acting on a body or an object i.e the sum of all forces acting simultaneously on a body or an object.
Mathematically, net force is given by the formula;
Where;
Fnet is the net force.
Fapp is the applied force.
Fg is the force due to gravitation.
In this scenario, a stalled car is being pushed up a hill at constant velocity by three people. Thus, the net force on the car is zero because all the forces acting on any physical object is equal to zero and represents a constant velocity; by balancing or cancelling each other out.
According to Sir Isaac Newton's First Law of Motion which is known as Law of Inertia, it states that an object or a physical body in motion will continue in its state of motion at continuous velocity (the same speed and direction) or, if at rest, will remain at rest unless acted upon by an external force.
Answer:
The capillary rise of the glycerin is most nearly 
Explanation:
From the question we are told that
The diameter of the glass tube is 
The density of glycerin is 
The surface tension of the glycerin is 
The capillary rise of the glycerin is mathematically represented as

substituting value


Therefore the height of the glass tube the glycerin was able to cover is
1. a. longitudinal waves.
There are two types of waves:
- Transverse waves: in transverse waves, the oscillations of the wave occur in a direction perpendicular to the direction of propagation of the wave
- Longitudinal waves: in longitudinal waves, the oscillations of the waves occur parallel to the direction in which the waves are travelling.
So, these types of waves are called longitudinal waves.
2. d. a medium
There are two types of waves:
- Electromagnetic waves: these waves are produced by the oscillations of electric and magnetic field, and they can travel both in a medium and also in a vacuum (they do not need a medium to propagate)
- Mechanical waves: these waves are produced by the oscillations of the particles in a medium, so they need a medium to propagate - therefore, the correct choice is d. a medium
3. a. AM/FM radio
Analogue signals consist of continuous signals, which vary in a continuous range of values. On the contrary, digital signals consist of discrete signals, which can assume only some discrete values. For AM and FM radios, signals are transmitted by using analogue signals.