SATHEE: Kinematics Question 181

Kinematics Question 181

Question: A body is thrown vertically upwards. If air resistance is to be taken into account, then the time during which the body rises is [RPET 2000; KCET 2001; DPMT 2001]

Options:

A) Equal to the time of fall

B) Less than the time of fall

C) Greater than the time of fall

D) Twice the time of fall

Show Answer

Answer:

Correct Answer: B

Solution:

Let the initial velocity of ball be u Time of rise $t_{1} = \frac{u}{g + a}$

and height reached $= \frac{u^{2}}{2 (g + a)}$

Time of fall $t_{2}$ is given by $\frac{1}{2} (g - a) t_{2}^{2} = \frac{u^{2}}{2 (g + a)}$
$\Rightarrow t_{2} = \frac{u}{\sqrt{(g + a) (g - a)}} = \frac{u}{(g + a)} \sqrt{\frac{g + a}{g - a}}$
$∴$ $t_{2} > t_{1}$ because $\frac{1}{g + a} < \frac{1}{g - a}$

Kinematics Question 181

Question: A body is thrown vertically upwards. If air resistance is to be taken into account, then the time during which the body rises is [RPET 2000; KCET 2001; DPMT 2001]

Options:

Answer:

Solution:

Engineering Preparation

Medical Preparation

NCERT Books & Solutions

Important Resources

Other Resources

Syllabus

Test Platform

Sample Mock Test

Mentorship

NCERT Exercise Video Solution

Kinematics Question 181

Question: A body is thrown vertically upwards. If air resistance is to be taken into account, then the time during which the body rises is [RPET 2000; KCET 2001; DPMT 2001]

Options:

Answer:

Solution:

Engineering Preparation

Medical Preparation

NCERT Books & Solutions

Important Resources

Other Resources

Syllabus

Test Platform

Sample Mock Test

Mentorship

NCERT Exercise Video Solution

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