Explanation

Concrete drying is a continuous and fluid event, and usually reaches its full effective strength after about 28 days.

Explanation

The troposphere is the lowest layer of Earth's atmosphere.

Most of the mass of the atmosphere is in the troposphere.

Most types of clouds are found in the troposphere, and almost all weather occurs within this layer.

Major layers are 

troposphere

stratosphere

mesosphere

thermosphere 

exosphere

Explanation

Photo resistors  are light sensitive variable resistors 

فوٹو ریزسٹرز روشنی کے حساس متغیر ریزسٹرس ہیں۔

Explanation

The minimum voltage which can flow current in the human body is 70 to 80 volts

 کم از کم وولٹیج جو انسانی جسم میں کرنٹ بہا سکتا ہے 70 سے 80 وولٹ ہے

Explanation

A balloon is filled with a gas called helium.

while

A balloon filled with hydrogen gas moves in the upward direction

Explanation

Earth has the highest density of any planet in the Solar System, at 5.514 g/cm3.

This is considered the standard by which other planet's densities are measured.

Explanation

Sunlight entering the water may travel about 1,000 meters into the ocean under the right conditions,

but there is rarely any significant light beyond 200 meters.

The ocean is divided into three zones based on depth and light level.

The upper 200 meters of the ocean is called the euphotic, or "sunlight," zone

ND5-07-2023

Explanation

Theodolite is a precision optical instrument for measuring angles between designated visible points in the horizontal and vertical planes.

Theodolite was invented by Leonard Digges (United Kingdom)

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Explanation

The speed of light is much faster than the speed of sound in air.

Light travels 186 thousand miles in 1 second, while sound takes almost 5 seconds to travel 1 mile

Light is a electromagnetic wave that's why it travel faster than sound wave however electromagnetic waves don't need medium to travel but sound wave need medium to travel

ND5-07-2023

Explanation

Three basic parts of an atom

1.   Electrons,

2.   Protons,

3.   Neutrons.

ND5-07-2023