The molecular geometry of \(NH_3\) and \(H_2O\) can be shown as:
The central atom \((N)\) in \(NH_3\) has one lone pair and there are three bond pairs. In \(H_2O\), there are two lone pairs and two bond pairs.
The two lone pairs present in the oxygen atom of \(H_2O\) molecule repels the two bond pairs. This repulsion is stronger than the repulsion between the lone pair and the three bond pairs on the nitrogen atom.
Since the repulsions on the bond pairs in \(H_2O\) molecule are greater than that in \(NH_3\), the bond angle in water is less than that of ammonia.
Match List-I with List-II and select the correct option: 
The bond angles \( b_1, b_2, b_3 \) in the above structure are respectively in \( ^\circ \):

Figure 8.9 shows the strain-stress curve for a given material. What are (a) Young’s modulus and (b) approximate yield strength for this material?

Two identical ball bearings in contact with each other and resting on a frictionless table are hit head-on by another ball bearing of the same mass moving initially with a speed V. If the collision is elastic, which of the following (Fig. 5.14) is a possible result after collision ?
