The Previous Week-1

A vector of magnitude 10 is added to a vector of magnitude 15. The magnitude of their sum might be:

• 3

• 15

• 12

• 5

Answer explanation

A train travels from one station to another at a speed of 40 m/s and returns to the first station at a speed of 60 m/s. What is the average speed of the train?

• 50 m/s

• 48 m/s

• 100 m/s

• 20 m/s

Answer explanation

Newton's Second Law states that:

• Acceleration is directly proportional to net force

• No force is needed to stop a moving body

• Action and reaction forces are equal and opposite

• Force is needed to start motion

Answer explanation

Explanation: Newton's Second Law:

F=ma

So, acceleration  is directly proportional to the net force .

A 60 kg man jumps down from a 0.8 m table. What is the speed when he hits the ground?

• 8 m/s

• 18 m/s

• 16 m/s

• 4 m/s

Answer explanation

Which medical imaging technique uses a high-frequency sound wave to create real-time images of the internal structure of the body?

• MRI

• PET

• Ultrasonic imaging

• Computer Tomography (CT)

Answer explanation

Explanation: Ultrasound imaging (or ultrasonic imaging) uses high-frequency sound waves to visualize internal organs.

In the figure below quadrilaterals ABCD and CDEF are similar and AB=10 cm, CD=8cm, AC=12cm and DE=6cm. The length of the CE is equal to:

• 6.4cm

• 7.2cm

• 7.5cm

• 9.6cm

In a triangle, the three interior angles are labeled as 4x∘, 2x∘, and 20∘. What is the value of x?

• 22∘

• 24∘

• 26∘

• 28∘

Which of the following is true about rationalizing the denominator?

• Only numerators can be rationalized when there is a radical.

• It is a technique of multiplying a given number by an irrational expression.

• Only denominators can be multiplied by an irrational number.

• It is a method of changing the denominator into a rational number.

When dividing 142 by 13 and expressed the result by applying the division algorithm, we get?

• 142 = 11(13) − 1

• 142 = 10(14) + 2

• 142 = 10(13) + 12

• 142 = 11(13) + 1