IBA STS MDCAT Past Paper 08-12-2024

Q131: If a force of 50 N is applied to a box of mass 2 kg for 2 seconds, what is the work done on the box?

2000 J

2500 J

3000 J

None of these

Q132: "The speed of light in the vacuum is the same for all observers regardless of their relative motion or the motion of the source of the light" is an important postulate of _______?

خلا میں روشنی کی رفتار تمام مبصرین کے لیے یکساں ہے قطع نظر ان کی نسبتی حرکت یا روشنی کے منبع کی حرکت _______ کا ایک اہم مؤقف ہے؟

Special theory of relativity

Special conductivity

Special resistivity

None of these

Explanation

This postulate, proposed by Einstein, is a cornerstone of the Special Theory of Relativity.

It states that the speed of light in a vacuum is constant (approximately $3 times 10^8$ m/s) and independent of the observer's or source's motion.

Q133: What is the hybridization of carbon in methanol (CH₃OH)?

میتھانول میں کاربن کی ہائبرڈائزیشن کیا ہے؟

sp³

sp

sp²

None of these

Explanation

In methanol, the carbon atom forms four sigma bonds: three with hydrogen atoms and one with the hydroxyl group (-OH).

This requires $sp^3$ hybridization, where one s orbital and three p orbitals combine to form four equivalent orbitals.

Q134: When two negative beta particles are emitted from a nucleus then the mass number _____?

جب ایک نیوکلئس سے دو منفی بیٹا ذرات خارج ہوتے ہیں تو ماس نمبر _____؟

Increases by 2

No change

Increases by 3

None of these

Q135: When magnetic field and area vector are perpendicular then magnetic flux will be ______?

جب مقناطیسی میدان اور ایریا ویکٹر کھڑے ہیں تو مقناطیسی بہاؤ ______ ہوگا؟

Minimum

Maximum

Zero

None of these

Q136: The force of repulsion is greatest between which of the following?

پسپائی کی قوت مندرجہ ذیل میں سے کس کے درمیان سب سے زیادہ ہے؟

Lone pair - Lone pair

Lone pair - Bond pair

Bond pair - Bond pair

None of these

Q137: In Cannizzaro reaction formaldehyde reads with which reagent?

کینیزارو کے رد عمل میں فارمل ڈیھائیڈ کس ری ایجنٹ کے ساتھ پڑھتا ہے؟

Ether

Methanol

NaOH

None of these

Q138: The gas law in which the pressure is kept constant is known as ______?

گیس کا وہ قانون جس میں پریشر کو مستقل رکھا جاتا ہے ______ کے نام سے جانا جاتا ہے؟

Charles' Law

Boyle's Law

Dalton's Law

None of these

Explanation

Charles's Law:

Volume ( $V$ ) is directly proportional to temperature ( $T$ ) at constant pressure.
Formula: $frac{V}{T} = k$ .

Boyle's Law:

Pressure ( $P$ ) is inversely proportional to volume ( $V$ ) at constant temperature.
Formula: $PV = k$

Ideal Gas Law:

Combines Charles's and Boyle's Laws. Relates pressure, volume, temperature, and moles of gas.
Formula: $PV = nRT$ , where $R$ is the gas constant and $n$ is the number of moles.

Q139: A man picks up a mass of 1 kg to a height of 1 meter. What is the work done by the man?

20 J

15 J

10 J

None of these

Explanation

Work done $W$ is calculated using the formula $W = mgh$ , where $m$ is mass, $g$ is acceleration due to gravity (9.8 m/s²), and $h$ is height.

W = 1 times 9.8 times 1 = 10 , text{J}

Q140: A Javelin is thrown by Arshad Nadeem at projection angle of 45 degrees with initial velocity of 30 m/s, the range of the Javelin will be (consider g = 10 m/s²)?

85m

95m

90m

None of these