The coefficient of cubical expansion of mercury is 0.00018/C and that of brass 0.00006/C. If a barometer having a brass scale were to read 74.5 cm at 30C, Find the true barometer height at 0C. the Scale is supposed to be corrected at 15C.

ANSWER : 74.122 cm

 

One end of a long metallic wire of length L is tied to the ceiling. The other end is tied to massless spring of spring constant k. A mass m hangs freely from the free end of the spring. The area of cross-section and Young's modulus of the wire are A and Y respectively. If the mass is slightly pulled down and released, it will oscillate with a time period T equal to

 

Class 9 Math Test Ch 1,2,3,4,5,7 FM 35

 

Class 9 First Unit Test Math ch 2,3,4, Physics ch 2 Motion in 1D FM 30

ANSWER

Mathematics: 

1. On a certain sum, the compound interest in 2 years amounts to Rs. 4240. If the rates of interest for successive years are 10% and 15% respectively, find the sum.

2. A man borrow Rs. 10,000 at 5% per annum compound interest. He repays 35% of the sum borrowed at the end of the first year and 42% of the sum borrowed at the end of the second year. How much must be pay at the end of the third year in order to clear the debt?

3. Class 9 Math ICSE SELINA compound interest EX 3B question 3 A sum of money lent out at C.I. at a certain rate per annum becomes three times of itself in 8 years. Find in how many years will the money becomes twenty-seven times of itself at the same rate of interest p.a.

4. Math Question Class 9 The value of the machine depreciated by 10% per year during the first two year and 15% per year during third year. Express the total depreciation of the machine, as percent, during the three years

5. Class 9 Math ICSE SELINA EXPANSION EX 4B question 16 If 4x^2+y^2=a and xy =b find the value of 2x+y

6. Class 9 ICSE Selina Math EX 4E question 5(i)

7.  Prove that x^2+y^2+z^2 -xy-yz-zx always positive

 

Class 11 | Elasticity | A uniform rod of mass M and length L is hanging from point P as shown in the figure. Find the elongation in its length due to the self weight of the rod. The Young's modulus of elasticity of the rod is Y and cross-sectional area of the rod is A .

 

Class 9 ICSE Selina Math EX 4E question 5(i)

Class 9 Math ICSE SELINA EXPANSION EX 4B question 16 If 4x^2+y^2=a and xy =b find the value of 2x+y

Prove that x^2+y^2+z^2 -xy-yz-zx always positive