Answer:gravity and friction
Explanation:Gravity to keep yourself on the ground and friction to not slide when are walking.
Answer:
Periodic.
Explanation:
Electromagnetic waves is a propagating medium used in all communications device to transmit data (messages) from the device of the sender to the device of the receiver.
Generally, the most commonly used electromagnetic wave technology in telecommunications is radio waves.
Radio waves can be defined as an electromagnetic wave that has its frequency ranging from 30 GHz to 300 GHz and its wavelength between 1mm and 3000m. Therefore, radio waves are a series of repetitive valleys and peaks that are typically characterized of having the longest wavelength in the electromagnetic spectrum.
Basically, as a result of radio waves having long wavelengths, they are mainly used in long-distance communications such as the carriage and transmission of data.
Generally, a fixed speed is used for the propagation of traveling waves and this speed is usually denoted with the variable "v" or sometimes "c."
Furthermore, if the waveform of a traveling wave is repeated every time at specific intervals T, it is referred to as periodic wave.
Mathematically, the period of a traveling wave is given by the formula;

Where;
T is the time measured in seconds.
Answer:
Part a)
distance = 112 miles
Part b)
current position = 112 miles from the position of town
Explanation:
Part a)
Since the distance marker is showing the distance between the town and the position of john at all time
so here we have

Part b)
Current position of John is given as

from the position of the town
When someone is struct by lightning, the electricity passes through the body, into the earth. Here, our body acts as a lightning conductor to complete the earthing process.
Answer:
(a) 0.3778 eV
(b) Ratio = 0.0278
Explanation:
The Bohr's formula for the calculation of the energy of the electron in nth orbit is:

(a) The energy of the electron in n= 6 excited state is:


Ionisation energy is the amount of this energy required to remove the electron. Thus, |E| = 0.3778 eV
(b) For first orbit energy is:




Ratio = 0.0278