Mechanism | MCQs

Explanation

Power is calculated as the rate of work done or energy transferred:

Power = Work / Time

= 20 J / 10 s

= 2 W

So, the machine's power output is 2 watts.

Explanation

She is used to face the hardships of life. 

Explanation

Inspiration, or inhalation, involves the contraction of two main muscle groups:

Diaphragm: a dome-shaped muscle that separates the chest cavity from the abdominal cavity.

When it contracts, it flattens and increases the volume of the chest cavity.

Intercostal muscles: muscles located between the ribs.

When they contract, they pull the ribs outward and upward, increasing the volume of the chest cavity.

Explanation

• The small intestine, also known as the small bowel, is the primary site of nutrient absorption in the human body.
• The walls of the small intestine are lined with finger-like projections called villi, which increase the surface area for absorption.
• Nutrients like carbohydrates, proteins, fats, vitamins, and minerals are absorbed into the bloodstream through the small intestine.

Explanation

• During swallowing, the epiglottis closes to cover the larynx (voice box).
• It preventing food and liquids from entering the trachea (windpipe).
• It directing them into the esophagus instead.

Explanation

• A gear (cog) is a toothed wheel that meshes with other gears to transmit rotational motion or change the direction of force.
• The pointed edges like teeth are used to engage with other gears and transmit power.

Explanation

• A car's steering system uses a wheel and axle.
• It is mechanism to transmit the rotational motion of the steering wheel to the wheels of the car, allowing the vehicle to turn.

Explanation

• Camels have a special water storage space in their humps, which store fatty tissue.
• When food and water are scarce, the camel's body metabolizes the fatty tissue in the hump, providing energy and water.
• This allows camels to survive for extended periods without water.