Question Discussion & Solution

Concept:

​Simple Pendulum:

• A simple pendulum consists of a small metallic ball or a piece of stone suspended from a rigid stand by a thread.
  The metallic ball is called Bob.
• A pendulum swings from one extreme position to another and comes back to the same position, this completes one oscillation. 
• One oscillation can also be defined as the pendulum starting from the mean position, going to one extreme, and coming back to the same mean position. 
• The time duration to compete for one oscillation is called time period and the is reciprocal of time period is frequency. 
• Frequency: The number of oscillations per unit time is called frequency. 

\(frequncy =\frac{Oscillation}{Time}\)

Calculation:

Given that : Frequency = 2 hz and time = 16 sec.

In a sec pendulum completes 2 oscillations per second.

⇒ Oscillations = Frequency × time

⇒ Oscillations = 2×16

⇒ Oscillations = 32

Additional Information

The time period of a simple pendulum depends upon on the length of the string and acceleration due to gravity.

\(T = 2 \pi \sqrt{\frac{l}{g}}\)

l is length, g is acceleration due to gravity. 

The pattern followed here is:

Similarly,

Hence, AHPSXMZD is the correct answer.

Explanation:

• Bronze is an alloy of copper and tin as the two main constituent elements.
• Bronze is a copper-based alloy that typically consists of approximately 88% copper and 12% tin.
• Some other elements added in minute quantities can be aluminium, nickel or zinc.
• It is one of the first alloys used by mankind and an entire era known as the 'Bronze Age' is known because of the extensive use of the alloy in many human artefacts.

Additional Information

Steel: 

• Stainless steel is an alloy of iron and chromium.
• Steel is an alloy of iron and carbon.
• Stainless steels are steels containing at least 10.5% chromium, less than 1.2% carbon, and other alloying elements.

Solder:

• Soldering is a joining process used to join different types of metals together having different properties. 
• Solder is a metal alloy, usually made up of tin and lead which is melted using a hot iron (soldering iron).
• The iron is heated to temperatures above 600˚F which then cools to create a strong bond.
• Flux material used in soldering is ZnCl2 (Zinc Chloride) and NH4Cl (Ammonium Chloride).

Brass:

• Brass is a metal alloy that is made up of copper and zinc.
• The proportions of zinc and copper can vary to create different types of brasses with different properties.
• It has higher malleability than bronze or zinc and has a relatively low melting point (900 to 940 °C).

Mistake Points

• Copper was the first metal used by men.
• Copper was first used by man over 10,000 years ago.  
• Probably copper can be found as a naturally occurring native metal that is sometimes found in large lumps on the ground.
• People learned to make this into copper tools and other things, although, for a metal, it is quite soft.
• When it was melted over the fire, people learned how to make an alloy called bronze, which is much harder and stronger than copper.

Let’s check each option,

Thus, the sequence is wxwzwy wxwzwy wxwzwy.

The correct answer is In 1600.

• In 1600, the East India Company was established.

Key Points

•  The Governor and company of merchants of London trading into the East Indies, popularly known as the English East India Company, were formed in 1600 AD.
• Captain William Hawkins arrived at Jahangir’s court (1609 AD) to seek permission to open a factory in Surat. A Farman was issued by Jahangir, permitting the English to build a factory in Surat (1613 AD).
• Sir Thomas Roe visited Jahangir’s court (1615 AD) as an ambassador of King James I to seek permission to trade in India.

Additional Information

• The Dutch East India Company established factories in India at Masulipatnam in 1605 AD, Pulicat (1610 AD), Surat (1616 AD), Bimlipatam (1641 AD), Karaikal (1645 AD).
• The French East India Company was formed in 1664 AD by Colbert under state patronage during the reign of Louis XIV.