A square copper plate of side 16 cm weighs 128 gm. A circular disc of diameter 14 cm is cut off from the plate. What is the weight of the remaining part? (\pi=\frac{22}{7})
- A. 48 gm
- B. 49 gm
- C. 50 gm
- D. 51 gm ✓
Correct Answer: D. 51 gm
Explanation
The density of the square plate is \frac{128}{16^2} = 0.5\text{ gm/cm}^2. The area of the cut circular disc is \pi r^2 = \frac{22}{7} \times 7^2 = 154\text{ cm}^2. The weight of the disc is 154 \times 0.5 = 77\text{ gm}. The remaining weight is 128 - 77 = 51\text{ gm}.
Related questions on Mensuration
- A pendulum swings through an angle of 30° and its end describes an arc of length 55 cm. What is the length of the pendulum? (Take $\pi = 22/...
- A conical tent has an angle of 60° at the vertex. If the curved surface area is 100 m^2, then what is the volume of the tent?
- A right circular cone and a hemisphere have equal base and equal volume. What is the ratio of the height of the cone to the radius of the he...
- A wire is in the form of an equilateral triangle with an area of 36\sqrt{3} cm^2. If it is changed into a semicircle, then what is its r...
- Let the area of the largest possible square inscribed in a circle of unit radius be x. Let the area of the largest possible circle inscribed...