Pakprep.com is equipped with all the relevant material which is helpful for students to prepare for any entry test. Pakprep.com contains over 15000 solved quality MCQ’s along with their explanation. We have 500 plus successful students from 2018 who got admission in different universities all over Pakistan after preparing from Pakprep.com. We have past papers which helps students to understand structure of entry test and difficulty of MCQ’s. We also provide the facility of MOCK test which will help the students to examine their current situation. Smart analytics will keep record of all your test according to subjects and topics. To start your preparation today with Pakprep.com please CLICK HERE.
Topic:
Fluid Dynamics
Question:
Water hose with internal radius of 0.01m has water flowing at the rate of 10 kg per 20s. What is the water speed at the outlet? Density of water is 1000 kg/m3.
Options:
Correct Option:
1.6m/s
Explanation:
From continuity equation A*V = flow rate of water = volume/s;
Volume/s = mass/s * density = 0.5/1000;
A*V = 0.5/1000; A = 3.14 * (0.01)2;
V = 0.5/ (3.14*(0.01)2*1000) = 1.6m/s
Topic:
Electromagnetism
Question:
The material used in florescent screen of CRO is?
Options:
- Magnesium
- Glass
- Phosphor
- Sodium
Correct Option:
Phosphor
Explanation:
A phosphor, most generally, is a substance that exhibits the phenomenon of luminescence. Somewhat confusingly, this includes both phosphorescent materials, which show a slow decay in brightness (>1 ms), and fluorescent materials, where the emission decay takes place over tens of nanoseconds.
Topic:
Nuclear physics
Question:
The energy obtained in a nuclear reaction is derived from:
Options:
- Mass defect and binding energy
- Fission
- Fusion
- All of these
Correct Answer:
All of these
Explanation:
The sum of the individual masses of the parts of a nucleus is less than their mass when they are bound into the nucleus producing mass defect. The mass from the mass defect is converted into the energy that holds the nucleus together and is released in fission. Fusion also produces energy when individual nuclei are forced to combine (fusion) and form new elements in a process that produces energy.
