SATHEE: Work Energy and Power - Result Question 5

Work Energy and Power - Result Question 5

7. A vertical spring with force constant $k$ is fixed on a table. A ball of mass $m$ at a height $h$ above the free upper end of the spring falls vertically on the spring so that the spring is compressed by a distance $d$ . The net work done in the process is

[2007]

(a) $m g (h + d) - \frac{1}{2} k d^{2}$

(b) $m g (h - d) - \frac{1}{2} k d^{2}$

(d) $m g (h + d) + \frac{1}{2} k d^{2}$

Show Answer

Answer:

Correct Answer: 7. (a)

Solution:

$= 8 + 5$

$= 13 J .$

. (a)

$W =$ Potential energy stored in the spring + Loss of potential energy of mass

$\Rightarrow W_{a} = - 8.75 J$

which is the work done due to air resistance

Work done due to gravity $= m g h$

$= 10^{- 3} \times 10 \times 10^{3} = 10 J$

$W = m g (h + d) - \frac{1}{2} k d^{2}$

Gravitational potential energy of ball gets converted into elastic potential energy of the spring.

$m g (h + d) = \frac{1}{2} k d^{2}$

Net work done $= m g (h + d) - \frac{1}{2} k d^{2} = 0$

$\frac{W_{P}}{W_{Q}} = \frac{\frac{1}{2} k_{p} x^{2}}{\frac{1}{2} k_{Q} x^{2}} = \frac{k_{p}}{k_{Q}}$

As $k_{p} > k_{Q}$ so, $W_{p} > W_{Q}$

Work Energy and Power - Result Question 5

7. A vertical spring with force constant $k$ is fixed on a table. A ball of mass $m$ at a height $h$ above the free upper end of the spring falls vertically on the spring so that the spring is compressed by a distance $d$ . The net work done in the process is

Answer:

Engineering Preparation

Medical Preparation

NCERT Books & Solutions

Important Resources

Other Resources

Syllabus

Test Platform

Sample Mock Test

Mentorship

NCERT Exercise Video Solution

Work Energy and Power - Result Question 5

7. A vertical spring with force constant k is fixed on a table. A ball of mass m at a height h above the free upper end of the spring falls vertically on the spring so that the spring is compressed by a distance d. The net work done in the process is

Answer:

Engineering Preparation

Medical Preparation

NCERT Books & Solutions

Important Resources

Other Resources

Syllabus

Test Platform

Sample Mock Test

Mentorship

NCERT Exercise Video Solution

Menu

7. A vertical spring with force constant $k$ is fixed on a table. A ball of mass $m$ at a height $h$ above the free upper end of the spring falls vertically on the spring so that the spring is compressed by a distance $d$ . The net work done in the process is