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1. Transmission of sound waves requires material medium but no material medium is required for electromagnetic waves
2. Speed of a sound wave is lower than that of an electromagnetic wave
johnmulu answered the question on February 11, 2017 at 08:19
- What is the difference between longitudinal and transverse waves?(Solved)
What is the difference between longitudinal and transverse waves?
Date posted: February 11, 2017. Answers (1)
- A spring extends by 6 cm when supporting a mass of 0.06 kg on earth. When the spring is used to support the same mass on the moon, it extends by 1 cm(Solved)
A spring extends by 6 cm when supporting a mass of 0.06 kg on earth. When the spring is used to support the same mass on the moon, it extends by 1 cm. Determine the moon's gravitational strength. (Take gravitational field strength on earth as 10 Nkg-1)
Date posted: February 11, 2017. Answers (1)
- A light spiral extends by 4 mm when loaded with a weight W. The spring is connected in series with an identical spring(Solved)
A light spiral extends by 4 mm when loaded with a weight W. The spring is connected in series with an identical spring. The combination is loaded with the weight W. Determine the extension of the combination.
Date posted: February 11, 2017. Answers (1)
- An object of weight 20 N attached at the end of a spring causes an extension of 0.5 cm on the spring(Solved)
An object of weight 20 N attached at the end of a spring causes an extension of 0.5 cm on the spring.
a) Determine the spring constant of the spring
b) Determine the weight of an object that would cause an extension of 0.86 cm when attached at the end of the same spring
Date posted: February 11, 2017. Answers (1)
- State the SI unit of a spring constant(Solved)
State the SI unit of a spring constant.
Date posted: February 11, 2017. Answers (1)
- You are provided with two wires of same material and same thickness. Describe how would make two spiral springs of different springs constants(Solved)
You are provided with two wires of same material and same thickness. Describe how would make two spiral springs of different springs constants (assume that other apparatus to make springs are available)
Date posted: February 11, 2017. Answers (1)
- State Hooke's law(Solved)
State Hooke's law.
Date posted: February 11, 2017. Answers (1)
- A wire fixed at one end extends by 4mm when a load of 20N is suspended from the other end. Determine the load that would cause an extension of 1.5 mm on the wire(Solved)
A wire fixed at one end extends by 4mm when a load of 20N is suspended from the other end. Determine the load that would cause an extension of 1.5 mm on the wire. (Assume elastic limit is not exceeded)
Date posted: February 11, 2017. Answers (1)
- State two ways in which the strength of an electromagnet can be increased(Solved)
State two ways in which the strength of an electromagnet can be increased.
Date posted: February 11, 2017. Answers (1)
- An electromagnet is made by winding insulated copper wire on an iron core. State two changes that could be made to increase the strength of the electromagnet(Solved)
An electromagnet is made by winding insulated copper wire on an iron core. State two changes that could be made to increase the strength of the electromagnet.
Date posted: February 11, 2017. Answers (1)
- State two ways of increasing the force on the coil(Solved)
State two ways of increasing the force on the coil.
Date posted: February 11, 2017. Answers (1)
- Why is the core of the electromagnet of an electric bell made of soft iron and not steel?(Solved)
Give reason why the core of the electromagnet of an electric bell is made of soft iron and not steel.
Date posted: February 11, 2017. Answers (1)
- State two factors that affect the strength of an electromagnet(Solved)
State two factors that affect the strength of an electromagnet.
Date posted: February 11, 2017. Answers (1)
- The force on a conductor carrying current in a magnetic field can be varied by changing among others, the magnitude of the current and the magnetic field strength(Solved)
The force on a conductor carrying current in a magnetic field can be varied by changing among others, the magnitude of the current and the magnetic field strength. Name two other factors that can be changed to vary the force
Date posted: February 9, 2017. Answers (1)
- State one application of each the following.
(i) Convex mirror
(ii) Parabolic mirror
(iii) Concave mirrors(Solved)
State one application of each the following.
i) Convex mirror
ii) Parabolic mirror
(iii) Concave mirrors
Date posted: February 7, 2017. Answers (1)
- A lady holds a large concave of focal length 1 m, 80 cm from her face. State two characteristics of her image in the mirror(Solved)
A lady holds a large concave of focal length 1 m, 80 cm from her face. State two characteristics of her image in the mirror
Date posted: February 7, 2017. Answers (1)
- A person carrying a heavy luggage using one hand leans away from the luggage. State the reason for this(Solved)
A person carrying a heavy luggage using one hand leans away from the luggage. State the reason for this.
Date posted: February 7, 2017. Answers (1)
- State the reason why a steel sphere resting on a horizontal surface is said to be in neutral equilibrium(Solved)
State the reason why a steel sphere resting on a horizontal surface is said to be in neutral equilibrium
Date posted: February 7, 2017. Answers (1)
- A uniform metal strip is 3.0 cm wide, 0.6 cm thick and d 100 cm long. The density of the metal is 2.7 g/cm3(Solved)
A uniform metal strip is 3.0 cm wide, 0.6 cm thick and d 100 cm long. The density of the metal is 2.7 g/cm3. Determine the weight of the strip
Date posted: February 7, 2017. Answers (1)
- State the principle of moments(Solved)
State the principle of moments
Date posted: February 7, 2017. Answers (1)