रासायनिक अभिक्रियाएं एवं समीकरण - L18 | NCERT Discussion Part 2 | CLASS10 विज्ञान | 8AM Nishtha mam

Class 10 Science (Hindi) | Chapter 1 | रासायनिक अभिक्रियाएँ एवं समीकरण | Important Questions | Quick Revision

A block A of mass 2 kg is placed over another block B of mass 8 kg and supported by a ledge L fixed on block B on its smooth surface as its extended part. If a force F=100 N is applied on block B , it starts moving on rough horizontal surface. Find the force exerted by block B on is 25 N . (Take g=10m//s^(2) )

For the reaction : N_2+3H_2 to 2NH_3 . If the rate of disappearance of hydrogen is 1.8 times 10^3 mol//l -sec . What is the rate of formation of ammonia?

The marks obtained by 40 students of class IX in an examination are given below: 18, 8, 12, 6, 8, 16, 12, 5, 23, 2, 16, 23, 2, 10, 20, 12, 9, 7, 6, 5, 3, 5, 13, 21, 13, 15, 20, 24, 1, 7, 21, 16, 13, 18, 23, 7, 3, 18, 17, 16 Present the data in the form of a frequency distribution using the same class size, one such class being 15-20 (where 20 is not included)

the daily minimum temperatures in degrees Celsius recorded in a certain Arctic region are as follows: -12. 5 ,-10. 8 ,-18. 6 ,-8. 4 ,-10. 8 ,-4. 2 ,-4. 8 ,-6. 7 ,-13. 2 , -11. 8 ,-2. 3 , 1.2 , 2.6 ,0,-2. 4 ,0, 3.2 , 2.7 , 3.4 ,0,-2. 4 ,-2. 4 ,0, 3. 2 , 2.7 , 3.4 ,0,-2. 4 ,-5. 8 ,-8. 9 ,-14 ,6,-12. 3 ,-11. 5 ,-7. 8 ,-2. 9 Represent them as frequency distribution table taking -19. 9\ to-15 as the first class interval.

In Fig. 16-13, two strings have been tied together with a knot and then stretched between two rigid supports. The strings have linear densities mu_(1) = 1.4 xx 10^(-4)" kg/m "and mu_(2)=2.8. xx 10^(-4)"kg/m". Their lengths are L_1= 3.0 m and L_2=2.0m, and string 1 is under a tension of 400 N. Simultaneously, on each string a pulse is sent from the rigid support end, toward the knot. Which pulse reaches the knot first. Figure 18-13 Two strings, of lengths L_1 and L_2 , tied together with a knot and stretched between two rigid supports.

Over the past 200 working days, the number of defective parts produced by a machine is given in the following table : |{:("Number of","0 1 2 3 4 5 6 7 8 9 10 11 12 13"),("defective parts",),("Days","50 32 22 18 12 12 10 10 10 8 6 6 2 2"):}| Determine the probability that tomorrow's output will have : (i) no defective part. (ii) at least one defective part, (iii) not more than 5 defective parts, (iv) more than 13 defective parts.