Explanation:
The given data is as follows.
mass (m) = 170 kg, Distance (s) = 9.6 m
Height (h) = 3.3 m, Force (F) = 1400 N
First, we will calculate the work performed by her as follows.
W = Fs
= 
= 13440 J
Hence, minimal work necessary to lift the refrigerator is as follows.
U = mgh
= 
= 5497.8 J
Therefore, we can conclude that he performed 5497.8 J of work.
Answer with Explanation:
We are given that
Resistance of solenoid,R=4.3 ohm
Magnetic field,B=
Current,I=4.6 A
Diameter of wire,d=0.5 mm=
Radius of wire,r=

Radius of solenoid,r'=1 cm=

Resistivity of copper,
We know that

Where 
Using the formula


Number of turns of wire=
Number of turns of wire=
Hence, the number of turns of the solenoid,N=799
Magnetic field in solenoid,B=






Length of solenoid=12.5 cm
1m=100 cm
Answer:
C. Quadruple
Explanation:
¨Drivers who are talking on the phone, even on a hands-free device, are up to four times more likely to be involved in a crash.¨
I hope this helps! Have a great day!
Electricity is NOT a part of electromagnetic spectrum.
An electromagnetic spectrum contains electromagnetic radiations arranged according to frequencies and wavelength.
<h2>Further Explanation
</h2><h3>Electromagnetic waves </h3>
- Electromagnetic waves are types of waves that do not require a material medium for transmission.
- These waves are mostly transverse in nature, which means the direction of transmission is perpendicular to the direction of vibration of particles.
- They include, light waves, radio waves, x-rays, infra-red, etc.
<h3>Electromagnetic spectrum
</h3>
- An electromagnetic wave shows electromagnetic waves arranged according to frequencies and wavelength.
- Electromagnetic spectrum contains electromagnetic waves: Gamma rays, x-rays, Ultraviolet, Visible light, infra-red, microwaves, and radio waves.
- The electromagnetic spectrum is divided into various sections based on wavelength, with gamma rays having the shortest wavelength and radio waves having the longest wavelength.
- The part of the electromagnetic spectrum that we can see using our naked eyes is called the visible light spectrum.
- In order of frequency, the radio waves have the lowest frequency while gamma rays have the largest frequency.
<h3>General characteristics of electromagnetic waves </h3>
- They travel with the speed of light (3.0 x 10^8 m/s)
- They possess energy that is given by; E =hf, where h is the plank’s constant and f is the frequency.
- They are transverse in nature, and therefore, the wavelength is measured between successful crests or troughs.
- They can travel through vacuum
Keywords: Electromagnetic spectrum, electromagnetic waves.
<h3>Learn more about: </h3>
Level: High school
Subject: Physics
Topic: Electromagnetic spectrum