NIOS Class 10 Science & Technology Chapter 10 Solution – Force And Motion
NIOS Class 10 Science & Technology Solution Chapter 10 Force And Motion. NIOS Class 10 Science & Technology Chapter 10 Question Answers Download PDF. NIOS Class 10 Science Notes.
NIOS Class 10 Science & Technology Chapter 10 Solution
|Subject||Science and Technology (212)|
|Topic||Question Answer, Solution, Notes|
CHAPTER: – 10
(Force And Motion)
INTEXT QUESTIONS 10.1
1) Is there any force applied when a cricket player changes the direction of ballby using his/her bat?
Ans: – Yes there works a force when a cricket player changes the direction of ball by using his or her bat.
2) Give an example from your daily life in which the shape of an object changes by applying a force.
Ans: – If we use the rubber f9r the working purpose then we will see that when pressure is exerted on that rubber it changes its shapes.
INTEXT QUESTIONS 10.2
1)What are balanced forces?
Ans: – We all know that forces acting on an object in a direction if at those forces is acting in the opposite direction then we say that its balanced forces.
2)Can a balanced force produces any acceleration in a body?
Ans: – No there is no possibility for the producing of balanced forces in a body.
3)what type of change can be produced by an unbalanced force in a body?
Ans: – The rest or motion state will change when the unbalanced force is present in our body.
INTEXT QUESTIONS 10.3
1) Why does water comes out from a wet piece of cloth when you shake it?
Ans: – The motion of water in the clothes makes it comes out when we shake those cloths. As the water try to remain in its position if shake the cloths and thus water came out.
2)Why do we fall forward, when a moving bus stops suddenly?
Ans: – The moment of inertia works in our body when we travel through the bus. It tries to remain in its position but the movement of bus makes it hampered.
3)Two similar trucks are moving on a road with the same velocity. One of them is empty while the other one is loaded. Which of the two has more momentum?
Ans: – We know that the momentum is the multiplication of the mass and the velocity. So which car has more mass will have more momentum. In the car which have more load will have more momentum.
4)If a body of mass 5 kg moves with a velocity of 10 ms–1, then what is the momentum of the body?
Ans: – Momentum=mass× velocity
5) Why does a boxer move his head backward while taking an oncoming punch?
Ans: – The boxer moves its hand backwards while taking an incoming punch because the boxer try to gain the extra motion which empower the punches.
INTEXT QUESTIONS 10.4
1) Why does a fast-moving car slow down when its engine is switched off?
Ans: – The engine of a car gave the moving thrust to the tyre of the cars as its speed up the when the engine start and when the engine stops after some times due to the friction motion the car stops.
2) Why do we slip when we step on a banana peel?
Ans: – If we step on the banana peel the at that time we slip because the motion of friction is working on that. Due to sliding motion we slip when we step in that.
3) Why are tyres of automobiles treaded?
Ans: – As treaded tyres provide better grip with the ground it uses in the automobile tyres.
INTEXT QUESTIONS 10.5
1)Why does a porter carrying a heavy load place a round piece of cloth on his head?
Ans: – As the round piece of cloth increases the area of contact between load and head of porter which helps in decreasing the pressure on his head.
2)Why a nail has a pointed tip?
Ans: – For the increases of the pressure a nail has a pointed tip.
3)Why shoulder bags are provided with broad straps?
Ans: – For the decreasing of pressure bags are provided with board straps.
4) State the SI unit of pressure.
Ans: – The SI unite of pressure is N/m^2 or in other words Pascal.
1) Why does a sprinter keep running for sometime even after crossing the finish line?
Ans: – When the running for the sometimes then thee works moment of inertia and in the sprinter, case there also works this simple formula. When the printer crosses the finishes line then also this moment of inertia moves it to some distance.
2) Why is it advised to tie the luggage with a rope on the roof of busses?
Ans: – When the bag is tied with the rope above the bus it stops the inertia motion of the bags after the starting of the bus. So,these bags remain in its position because of tied it.
3) Why do the dust particles from the hanging blanket fall off when it is beaten with a stick?
Ans: – The dust particles in a blanket try to maintain in states of motion but the shaking of the blanket makes the particles moves around. So, the inertia of the particles does that job.
4) State Newton’s first law of motion. Why do the passengers standing in a stationary bus fall in the backward direction when the bus begins to move suddenly?
Ans: – The Newton first law of motion stats that if we don’t exert pressure from the outside then the moving particles and the object which is in its position always try to remain in its position.
As a result of that we see the bus when suddenly move our body also moves in that direction because of moment of inertia.
5) Define momentum. How the rate of change of momentum is related to force?
Ans: – The momentum is the multiplication of the mass and the velocity. As we all know that forces depend on the mass and the acceleration which is dependent on the velocity so changes in the momentum makes the forces changes.
6) If a body of mass 10 kg moves with a velocity of 7 ms–1, then what is the momentum of the body?
Ans: – Momentum= mass × velocity
Or, momentum= 10 × 7= 70.
7) If a force of 50 N acts on a body of mass 10 kg then what is the acceleration produced in the body?
Ans: – We know that force, F= m × a.
Here, a = acceleration=?; mass=10kg, f=50N.
So, 50= a × 10;
Or, a=5 m/s^2.
8) State Newton’s third law of motion. Why it is difficult for a fireman to hold ahose pipe which ejects larger amount of water at a high speed?
Ans: – Newton third law states that each force has will has equal and opposite forces.
When the water is ejected from the hose pipe at that time each amount of force is needed from the hand to hold it. As the hand doesn’t provide same number of forces it is difficult to hold it.
9)“Action and reaction forces are equal in magnitude and opposite in direction”. Then, why do they not balance each other?
Ans: – Although the action and reaction forces are equal in magnitude and opposite in direction but all times that forces aren’t balanced. Because of the different number of sources of forces the action and reaction forces are not equal.
10) A motorcycle is moving with a velocity of 72 km/h and it takes 6 s to stop after the breaks are applied. Calculate the force exerted by the breaks on the motorcycle, if its mass along with the rider is 175 kg.
Ans: – Initial velocity(u)= 72 km/h = 72×5/18 = 20m/s.
Final velocity= 0; time=6s.
So, v= u + a×t,
Or, a=-20/6 =- 10/3.
Then force = mass× acceleration= 175× -10/3= 583.33N.
11) An object of mass 2 kg travelling in a straight line with a velocity of 10ms–1 collides with and sticks to a stationary object of mass 6 kg. Then they both move off together in the same straight line. Calculate the total momentum just before the impact and just after the impact.
Ans: – Momentum= mass × velocity;
Here, mass= (2 + 6) = 8kg. And velocity= 10m/s.
So, momentum= 8×10= 80. Khm/s^2.
12)What is the force of friction? State two methods to reduce friction.
Ans: – The force of friction is the restricted force principal when an object is moving slow its speed.
Method for the reduction of friction: –
- Using lubricating oil.
- By polishing the surface.
13) What is the relation between thrust and pressure? State the SI units of thrust and pressure. Why a camel can run in a desert easily?
Ans: – Thrust and pressure are directly proportional to each other.
The SI unit of thrust is Newton and the pressure is Pascal.
Because of having wide feet and the long leg the camel loses its weight in the sand and as a result of that easily runs on the surface of the desert.
14) A block of wood kept on a table applies a thrust of 49 N on the table top. The dimensions of the wooden block are 40 cm × 20 cm × 10 cm. Calculate the pressure exerted by the wooden block if it is made to lie on the table top with its sides of dimensions (a) 20 cm × 10 cm and (b) 40 cm × 20 cm.
Ans: – We know that, pressure = force/ area,
Case: – 1;
Here area = 20×10 cm^2 = 0.2× 0.1 m^2.
So, pressure= 49 / (0.2 × 0.1) =2450pa.
Case: – 2;
Here, area= 40× 20 cm^2 = 0.4 × 0.2 m^2.
So, pressure= 49 / (0.4 × 0.2) =612.5 pa.