Tutor profile: Nikhar M.

A body of mass 5kg is travelling according to the following law : x(t) = 15t + 6t^2 + 3t^3 (t is time). Find the force acting on the body at t=1 second.

Newton' s Second Law of Motion can be written as F = ma; where F is a net force acting on the body, m is the mass of the body and a is the body's acceleration. Now, we have the trajectory equation of the body as a function of time. To find the velocity of the body as a function of time, we differentiate x(t) with respect to t: Thus, v(t) = 15 + 12t + 9t^2. To find the acceleration of the body as a function of time, we differentiate v(t) with respect to t: Thus, a(t) = 12 + 18t. Now, acceleration at t=1 can be found by just substituting t=1 in a(t), thus finding a(1). a(1) = 12 + 18*1 = 30 Net force can be found by F = m*a. F = 5kg * 30m/s^2 = 150 kg-m/s^2 = 150 N

Find the molecular formula of a compound whose empirical formula and molecular masses are CH2O and 180 gram respectively.

The empirical formula of a compound shows the ratio of various elements in it. Seeing CH2O, we can say that the molecular formula of the compound has x atoms of C, 2*x atoms of H and x atoms of O. let's assume the compound is CxH2xOx. So, it will weigh : (12x + 2x + 16x) = 30x = 180(given) x = 180/30 = 6 Formula will be C6H12O6.

Find out the error in the following code snippet in C programming language. #include <stdio.h> int main(){ int a; char t; scanf(" %c ", &a); scanf(" %d ", &t); printf(" %c %d ", t,a); return 0; }

The first thing that I have observed is that 'a' has been declared as an integer but input is taken for it with '%c' format specifier which is a character. This would not generate an error since C language supports implicit 'type-casting', thus, the character would be changed to integer and stored in a. However, when specifier is '%d' and the variable is of character type, it would generate an error as here 'int' won't be typecasted to a 'char'. Thus, the scanf statement in line 6 would give an error. To remove the error, you can just correct the scanf statements and replace a and t in them.