Answer:
option(d)
Explanation:
The frequency of a wave is the property of the source of wave.
The velocity of all the electromagnetic waves is same as the speed of light. It only changes as the light passes through one medium to another.
The frequency is defined as the number of waves coming out from the source in 1 second.
As the frequency of wave increases, the number of wave coming per second increases.
So, the number of waves passing by increases but the speed remains same.
Option (d)
I'll assume that the chair has four legs.
Since the chair weights 3.7 kg by itself, it will weigh (79+3.7)=82.7 kg with the person sitting on it. And each of the chair's legs will take about (82.7/4)=20.675 kg.
Each leg touches the floor in a circle with 1.3cm diameter. The area of that circle is about (3.14*(1.3/2)^2)=1.327 cm^2.
Pressure is measured by force per area. So, the pressure from each leg is about 20.675kg / 1.327cm^2. That simplifies to 15.58 kg/cm^2.
Answer: opening of the nicotinic acetylcholine receptor channels.
Explanation:
Neuromuscular junction is a special junction formed between a motor neurone and a muscle fibre. The junction is fortified with nerves and receptors that helps in the transmission of signals from the motor neurone to the muscle fibre in order to bring about the desired voluntary movements through muscular contraction.
Nicotinic acetylcholine receptor are activated through the binding of acetylcholine at the neuromuscular junction. This action leads to influx of sodium ions to accomplish endplate potential.
Answer:
Constant speed: yes
Constant velocity: no
Explanation:
Let's remind the definition of speed and velocity:
- Speed is a scalar quantity, which is equal to the ratio between the distance covered (regardless of the direction) and the time taken:

- Velocity is a vector quantity, so it has both a magnitude and a direction. The magnitude is equal to the rate between the displacement of the object and the time taken, while the direction is the same as the displacement.
In this problem, we notice that:
- The speed of the car remains constant, as it is 90 km/h
- However, its direction of motion changes while the car travels round the corner: this means that the direction of the velocity is also changing, therefore velocity is not constant.
All wheelchairs may be secured
so that the user is facing the curb side of the vehicle is true. The answer is
letter A. It provides a unique 180 degree powered rotation which makes it
possible to raise, lower and rotate fully.