Get Answers to all your Questions

header-bg qa

A student records the initial length l, change in temperature \Delta T and change in length \Delta l of a rod as follows:

S.No

l (m)

\Delta T (^{\circ}C)

\Delta l (m)

1

2

10

4 \times 10^{-4}

2

1

10

4 \times 10^{-4}

3

2

20

2 \times 10^{-4}

4

3

10

6 \times 10^{-4}

If the first observation is correct, what can you say about observations 2, 3, and 4.

Answers (1)

\Delta t is same here.

Now, from observation no. 1

\alpha =\frac{\Delta L}{L \Delta t}

   \frac{4 \times 10^{-4}}{2 \times 10}= 2 \times 10^{-5} C^{\circ}-1

Now, for observation no. 2,

\Delta L=\alpha L \Delta t

    = 2 \times 10^{-5} \times 1 \times 10

    = 2 \times 10^{-4}m viz. not equal to 4 \times 10^{-4}m

Now, for observation no. 3,

\Delta L=\alpha L \Delta t
   = 2 \times 10^{-5} \times 2 \times 20

   = 8 \times 10^{-4} viz. not equal to = 2 \times 10^{-4}m

Now, for the last observation, i.e., no. 4,

\Delta L=\alpha L \Delta t

  = 2 \times 10^{-5} \times 3 \times 10

    = 6 \times 10^{-4 }= 6 \times 10^{-4}m.

Posted by

infoexpert24

View full answer