Doubtly
@Doubtly · Joined Feb 2021
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- What are the types of particles in each of the four main classes of crystalline solids ? In each of the four main classes of crystalline solids, the smallest constituents or particles of various solids are atoms, ions or molecule... 2
- Pb has fcc structure with edge length of unit cell 495 pm. Radius of Pb atom is Correct option is d. 175 pm 2
- A compound forms hcp structure. Number of octahedral and tetrahedral voids in 0.5 mole of substance is respectively a. 3.011×10²³, 6.022×10²³ 2
- Which of the following is not correct? a. Four spheres are involved in the formation of tetrahedral void. c. If the number of atoms is N the number of octahedral voids is 2N. 1
- The coordination number of atoms in bcc crystal lattice is a. 2 b. 4 c. 6 d. 8 correct option is d) 8 2
- In crystal lattice formed by bcc unit cell the void volume is a. 68 % b. 74 % c.32 % d. 26 % c.32 % correct option is c.32 % 2
- In Frenkel defect a. electrical neutrality of the substance is changed d. overall electical neutrality is preserved. 2
- Which of the following is n-type semiconductor? a. Pure Si b. Si doped with As c. Si doped with Ga b. Si doped with As 2
- You are on a long downhill slope. What should you do to help control the speed of your vehicle ? change to low gear 2
- It is essential to wear a helmet while driving a two-wheeler because It is for your individual safety & by Rule also. 2
- A flashing yellow signal is used when you should slow down & proceed with caution 2
- You stop for pedestrians waiting to cross at a zebra crossing. They do not start to cross. What should you do ? be patient and wait 2
- You are allowed to park neither of these two alternatives 2
- A high beam in foggy conditions is bad because it reflects back and can dazzle 2
- When approaching a crossing where you are to go straight change lanes at least 50 mts ahead to the middle lane 2
- You are driving. A vehicle comes up quickly behind, flashing head lamps. You should allow the vehicle to over take, if safe & with proper signal 1
- When must you use a dipped / high beam headlight during the day ? In poor visibility and highways 2
- You are driving in rain. Why should you keep well back from the vehicle in front ? in case it stop suddenly 2