Solve the following examples / numerical problems:
A 100 kg bag of wheat is placed on a plank of wood. What is the weight of the bag and what is the reaction force exerted by the plank ?

Solve the following examples / numerical problems: How many calories of heat will be absorbed when 3 kg of ice at 0⁰ C melts ?

Solve the following examples / numerical problems: If the weight of a body on the surface of the moon is 100 N , what is its mass ?

Solve the following examples / numerical problems: An object takes 5 s to reach the ground from a height of 5 m on a planet . What is the value of g on the planet ?

Solve the following examples / numerical problems: A metal ball of mass 5 kg falls from a height of 490 m. How much time will it take to reach the ground ?

Solve the following examples / numerical problems: The mass of the earth is 6xx10^24 kg. The distance between the earth and the sun is 1.5xx10^11m. If the gravitational force between the two is 3.5xx 10^22 N, what is the mass of the Sun ? ( use G =6.7xx 10^-11 Nm^-2kg^-2)

Solve the following examples/ numerical problems: An object is placed at 10 cm from a convex lens of focal length 12 cm . Find the nature and position of the image .

Solve the following examples/numerical problems : If the mass of a planet is 8 times that of the earth and its radius is twice the radius of the earth , what will be the escape velocity for that planet?( Escape velocity for the earth=11.2 km/s)

Solve the following examples/numerical problems : If the mass of a planet is eight times the mass of the earth and its radius is twice the radius of the earth, what will be the ratio of the escape velocity on the earth to the escape velocity on the planet?

Solve the following examples (numerical problems): If a charge of 420 C flows through a conducting wire in 5 minutes what is the value of the current?