1. False
2. True
3. True
4. False
5. True.
6. False.
7. True.
8. False.
9. False.
10. True.
11. False.
<h3><u>Explanation</u>:</h3>
A wave is a disturbance in a medium which can propagate through a medium. But the net displacement of the medium remains zero.
The spreading of the wave from a slit or hole is proved through the double slit experiment showing interference between the two waves. So they do spread by passing through a hole.
A longitudinal wave is what is seen when a stone is thrown into a pond. The ripples created are the compression points and the areas between the two ripple is called the rarefaction point.
Amplitude is defined as the maximum displacement of a particle in wave from its mean position. So its not distance between two compression points.
2nd law of reflection states that the angle of incidence is equal to angle of reflection.
An electromagnetic wave doesn't need a matter to get transferred. Its the electric field and magnetic field vibrating at same interval but in 90°to each other.
Mechanical wave needs matter to transfer energy. So it cannot travel through space.
Decibel is the unit of intensity of sound. Unit of frequency is hertz or cps.
Answer:
The correct answer is option C.
Explanation:
Single replacement reaction : It is a type of chemical reaction in which element exchange their position with the position of another element in its compound molecule.

It is also called redox reaction because one element getting oxidized and another one getting reduced.
Hence, the correct answer is option C.
Here we have to point out the necessary character of the substance needed which are used as lightning conductor.
The substance should have the following properties:
High electricity carrying capacity and less resistant.
High melting point
The substance should have high electricity carrying capacity or the resistance is less so that the electricity generated during the lightning easily conducted to the ground
The substance should have high melting point so that during lightning the generated high temperature cannot disrupt the material.
Titration experiments require the use of a burette. It is a long graduated glass tube held in place by a clamp stand. It has a tap fixture on the end that regulates the delivery of small volumes of liquid into a beaker in the titration process. Bunsen burners are used to heat substances and crucibles are used to hold items to be heated to high temperatures.
Answer:
We have to fill the acetylene tank with a pressure of 60.67 atm to ensure that you run out of each gas at the same time
Explanation:
Step 1: Data given
Volume of tank 1 = 6.50 L = oxygen
Volume of tank 2 = 4.50 L = acetylene
Pressure in the oxygen tank = 105 atm
Step 2: The balanced equation
2 C2H2 + 5 O2 → 4 CO2 + 2 H2O
For 2 mol C2H2 we need 5 moles O2 to produce 4 moles CO2 and 2 moles H2O
Step 3: Calculate the pressure of the acetylene tank
For 2 mol C2H2 we need 5 moles O2 to produce 4 moles CO2 and 2 moles H2O
This means for each 5 moles O2 we have 2 moles acetylene
Pressure (105 atm) * (2/5) * (6.50 / 4.50) = 60.67 atm
We have to fill the acetylene tank with a pressure of 60.67 atm to ensure that you run out of each gas at the same time