Question Discussion & Solution

1) × and ÷

Given statement: 46 ÷ 2 -­ 7 × 3 + 5 = 39

On interchanging the above signs,

46 × 2 ­- 7 ÷ 3 + 5

= 46 × 2 ­- 2.33 + 5

= 92 ­- 2.33 + 5

= 97 -­ 2.33

= 94.67 ≠ 39

2) ­- and ×

Given statement: 46 ÷ 2 -­ 7 × 3 + 5 = 39

On interchanging the above signs,

46 ÷ 2 × 7 -­ 3 + 5

= 23 × 7 -­ 3 + 5

= 161 ­- 3 + 5

= 166 ­- 3

= 163 ≠ 39

3) + and ×

Given statement: 46 ÷ 2 -­ 7 × 3 + 5 = 39

On interchanging the above signs,

46 ÷ 2 7 + 3 × 5

= 23 ­- 7 + 3 × 5

= 23 ­- 7 + 15

= 38 7

= 31 ≠ 39

4) + and ­-

Given statement: 46 ÷ 2 -­ 7 × 3 + 5 = 39

On interchanging the above signs,

46 ÷ 2 + 7 × 3 ­- 5

= 23 + 7 × 3 ­- 5

= 23 + 21 ­- 5

= 44 -­ 5

= 39

The correct answer is 240 J.

Key Points

• When a force is applied to an object which causes displacement along the direction of force then the work is said to be done by that force.
• The work done by a force is defined as "the product of the component of the applied force on the block in the direction of the displacement and the magnitude of this displacement" is called work done.

Additional Information

• i.e., \(W = \vec F.d\vec x = Fdx\cos \theta \)

or in terms of magnitude, it can be given as

\(W\; = \;F \times s\)

• Here both force and displacement will be along the same direction since force is causing this displacement thus Work done is a scalar quantity.
  • Here,
  • Force applied on object = F
  • Displacement of object = dx
  • Distance traveled by an object = s
  • The angle between Force and displacement = θ
• Calculation:
  • Given that,
  • Person raised the box of weight 120 N through the height of 2 m
  • i.e., F = 120 N 
  • x = 2 m
• Thus from the above explanation, we can see that
• Work = Force × Distance moved in the direction of the force
• Force of 120 N is acting downwards, Therefore
  • Work Done = 120 × 2 = 240 J

The correct answer is ​Heat is absorbed.

Key Points

•  When ice is converted into water heat is absorbed by the ice, so the molecules of ice increase their energy and convert into water. Hence option A is correct.
• Additional Information
• The conversion of ice into water is an example of melting. If you took out the ice cubes from the freezer and placed them in a warm room, the ice would absorb energy from the warmer air around them. This absorbed energy would facilitate them to overcome the force of attraction holding them together, enabling them to slip out of the fixed position that they held as ice. The process in which solids change to a liquid is called melting. The melting point is the temperature at which a solid changes to a liquid. 
• The static water is converted to ice It means when the water is converted into ice its potential energy decreases. 
• If we compare the kinetic and potential energy of the water vapor, water and ice then water vapor has the most kinetic as well as potential energy as compared to water and ice.
• This is because the particle of water vapor is free to move and they can move more vigorously. Please note that kinetic energy is associated with moving objects whereas potential energy is associated with a static object. 

The correct answer is Magh Krishna​ Chaturthi.

Key Points

• Tilkut Chauth-
  • It is celebrated on Magh Krishna Chaturthi.
  • It is also known as Sakat Chauth.
  • Ganesh Ji and Chauth Mata are worshiped on this occasion.
  • In Chauth Ka Barwara, Sawai Madhopur, a fair is organized.

Additional Information

• Karwa Chauth -
  • It is celebrated on Kartik Krishna Chaturthi.
  • Women do fast of  Chauth Mata on this day, For long age of their husband.
• Ganesh Chaturthi-
  • It is celebrated on Bhadrapad Shukla Chaturthi.
  • A fair is organized in Ranthambhore, Sawai Madhopur on this day.
• Gor Fair-
  • It is celebrated on Vaisakh Shukla Chaturthi.
  • It is organized in Siyawa, Abu Road.

Given series U, R, O, L, I, ?

We subtract 3 in each letter we get-

Hence, "F" is the correct answer.