First Law of Motion

Q.

Write any 10 examples of pull.

Q.

Two forces ${\mathrm{F}}_1=1\mathrm{N}$ and ${\mathrm{F}}_2=2\mathrm{N}$ act along the lines $\mathrm{x}=0$ and$\mathrm{y}=0$respectively. Then, the resultant of forces would be

1. $\hat{\mathrm{i}}+2\hat{\mathrm{j}}$

2. $\hat{\mathrm{i}}+\hat{\mathrm{j}}$

3. $3\hat{\mathrm{i}}+2\hat{\mathrm{j}}$

4. $2\hat{\mathrm{i}}+\hat{\mathrm{j}}$

Q.

A gas-filled balloon moves up. Is the upward force acting on it larger or smaller than the force of gravity?

Q. Paragraph for below question
नीचे दिए गए प्रश्न के लिए अनुच्छेद

When an object follows a circular path at constant speed, the motion is called uniform circular motion. When taking centre of circle at origin, the equation of circle is x² + y² = r², where r is radius of circle. The velocity of the object is continuously changing in direction and object undergoes acceleration.

In uniform circular motion, magnitude of acceleration towards centre of circle is $\left(\frac{v^2}{r}\right)$. Now answer the following question.

जब एक वस्तु नियत चाल से वृत्तीय पथ का अनुसरण करती है, तब गति को एकसमान वृत्तीय गति कहा जाता है। जब वृत्त के केन्द्र को मूल बिन्दु पर लिया जाता है, तब वृत्त की समीकरण x² + y² = r² है, जहाँ r वृत्त की त्रिज्या है। वस्तु के वेग की दिशा मे निरन्तर परिवर्तन हो रहा है तथा वस्तु त्वरित होती है।

एकसमान वृत्तीय गति में, वृत्त के केन्द्र की ओर त्वरण का परिमाण $\left(\frac{v^2}{r}\right)$ है। अब निम्नलिखित प्रश्न का उत्तर दीजिए।

Q. A particle is moving with constant speed over a circle x² + y² = 50 with speed $\sqrt{10}m/s$, then (x and y are in metre)

प्रश्न - एक कण वृत्त x² + y² = 50 पर नियत चाल $\sqrt{10}m/s$ से गतिशील है, तब (x तथा y मीटर में हैं)

1. Radius of circular path is 50 m
   
   वृत्तीय पथ की त्रिज्या 50 m है
2. Velocity of the object remains constant
   
   वस्तु का वेग नियत रहता है
3. Magnitude of acceleration of the particle is $\sqrt{2}m{s}^{-2}$
   
   कण के त्वरण का परिमाण $\sqrt{2}m{s}^{-2}$ है
4. Angular velocity of the particle is variable
   
   कण का कोणीय वेग परिवर्ती है

Q. Which of Newton's Laws explains why satellites need very little fuel to stay in orbit?

1. $1^{st}$ Law
2. $2^{nd}$ Law
3. $3^{rd}$ Law
4. Law of conservation of mass

Q.

When a force is applied to a body its shape changes.

1. Always

2. Never

3. Maybe

Q. Resultant of two forces ${\overrightarrow{F}}_{1}and{\overrightarrow{F}}_2$ has magnitude of 100 N. The resultant is inclined to ${\overrightarrow{F}}_1$ at 53° and to ${\overrightarrow{F}}_2$ at 37º. Magnitudes of ${\overrightarrow{F}}_{1}and{\overrightarrow{F}}_2$ respectively are

दो बल ${\overrightarrow{F}}_1$ तथा ${\overrightarrow{F}}_2$ के परिणामी का परिमाण 100 N है। परिणामी, ${\overrightarrow{F}}_1$ से 53° पर आनत है तथा ${\overrightarrow{F}}_2$ से 37° पर आनत है। ${\overrightarrow{F}}_1$ तथा ${\overrightarrow{F}}_2$ के परिमाण क्रमशः हैं

1. 50 N, 50 N
2. 80 N, 60 N
3. 60 N, 80 N
4. $50N,50\sqrt{3}N$

Q. Which of the following is true if the net external force on a body is zero?

1. Its acceleration is zero.
2. Its velocity remains constant.
3. Both (a) and (b)
4. None of these

Q.

In Galileo's experiment in order to reach the same height how far must the ball go on the horizontal surface after being released from an incline of a height of 5m?

1. 0 m

2. 5 m

3. 10 m

4. Infinity

Q. When a moving bus stops immediately , you feel a push forward because of.

1. friction
2. back seat
3. your own inertia
4. gravity

Q. 1 newton is equal to

1. 1 kg m/s
2. 1 kg m/s/s
3. 1 kg m s
4. None of these

Q. More than One Answer Type
एक से अधिक उत्तर प्रकार के प्रश्न

A ball is projected from the top of a tower of height 80 m, with speed 50 m/s at an angle 37° above the horizontal. Which of the following statement(s) is/are correct? (g = 10 m/s²)

एक गेंद को 80 m ऊँचाई की एक मीनार के शिखर से क्षैतिज से 37° कोण पर 50 m/s चाल से प्रक्षेपित किया जाता है। निम्नलिखित में से कौनसा/कौनसे कथन सही है/हैं? (g = 10 m/s²)

1. Total time of flight of ball is 8 second
   
   गेंद का कुल उड्डयन काल 8 सेकण्ड है
2. Maximum height reached by the ball from ground is 125 m
   
   धरातल से गेंद द्वारा प्राप्त की गई अधिकतम ऊँचाई 125 m है
3. Speed of particle on reaching the ground is 50 m/s
   
   धरातल पर पहुँचने पर कण की चाल 50 m/s है
4. Total time of flight of ball is 6 second
   
   गेंद का कुल उड्डयन काल 6 सेकण्ड है

Q.

From rest you suddenly stand up and start walking. But according to Newton's first law there has to be a force for change of state. What force made you move?

1. Muscular force of your Muscles

2. Chemical force of the food you ate

3. Normal force of Earth as you push the ground to walk

4. Friction force by ground

Q.

Statement I A cloth covers a table. Some dishes are kept on it. The cloth can be pulled out without dislodging the dishes from the table.
Statement II For every action there is an equal and opposite reaction.

1. If statement I is true, Statement II is true; statement II is the correct explanation for statement I

2. If statement I is true, Statement II is true; statement II is not a correct explanation for statement I

3. If statement I is true; statement II is false

4. If statement I is false; statement II is true

Q.

A force has been applied on a ball when it is

1. kicked

2. pushed

3. thrown

4. All of these

Q. Which of the following is true if the net external force on a body is zero?

1. Its acceleration is zero.
2. Its velocity remains constant.
3. Both (a) and (b)
4. None of these

Q.

The natural state of things is to be at rest.
Is the above statement True?

1. True

2. False

Q. The natural state of things is to be at rest.

1. True
2. False