362272
A body is thrown vertically upwards. If air resistance is to be taken into account, then the time during which the body rises is
1 Greater than the time of fall
2 Twice the time of fall
3 Equal to the time of fall
4 Less than the time of fall
Explanation:
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 is given by \(\frac{1}{2}(g - a)t_2^2 = \frac{{{u^2}}}{{2(g + a)}}\) \( \Rightarrow {t_2} = \frac{u}{{\sqrt {(g + a)(g - a)} }}\) \(\therefore {t_2} > {t_1}\) because \(\frac{1}{{g + a}} < \frac{1}{{g - a}}\)
PHXI03:MOTION IN A STRAIGHT LINE
362273
The graph shows position as a function of time for two trains running on parallel tracks. Which one of the following statements is true?
1 At time \({t_{B}}\), both trains have the same velocity.
2 Both trains have the same velocity at some time after \({t_{B}}\).
3 Both trains have the same velocity at some time before \({t_{B}}\).
4 Somewhere on the graph, both trains have the same acceleration.
Explanation:
Slope of curve \({B}\) and slope of curve \({A}\) is same before time \({T_{B}}\) only. Acceleration of \({A}\) is always zero, whereas that of \({B}\) is not zero.
PHXI03:MOTION IN A STRAIGHT LINE
362274
The displacement-time graphs of two moving particles make angles of \(30^\circ \) and \(45^\circ \) with the \(x\)-axis as shown in the figure. The ratio of their respective velocities is:
362272
A body is thrown vertically upwards. If air resistance is to be taken into account, then the time during which the body rises is
1 Greater than the time of fall
2 Twice the time of fall
3 Equal to the time of fall
4 Less than the time of fall
Explanation:
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 is given by \(\frac{1}{2}(g - a)t_2^2 = \frac{{{u^2}}}{{2(g + a)}}\) \( \Rightarrow {t_2} = \frac{u}{{\sqrt {(g + a)(g - a)} }}\) \(\therefore {t_2} > {t_1}\) because \(\frac{1}{{g + a}} < \frac{1}{{g - a}}\)
PHXI03:MOTION IN A STRAIGHT LINE
362273
The graph shows position as a function of time for two trains running on parallel tracks. Which one of the following statements is true?
1 At time \({t_{B}}\), both trains have the same velocity.
2 Both trains have the same velocity at some time after \({t_{B}}\).
3 Both trains have the same velocity at some time before \({t_{B}}\).
4 Somewhere on the graph, both trains have the same acceleration.
Explanation:
Slope of curve \({B}\) and slope of curve \({A}\) is same before time \({T_{B}}\) only. Acceleration of \({A}\) is always zero, whereas that of \({B}\) is not zero.
PHXI03:MOTION IN A STRAIGHT LINE
362274
The displacement-time graphs of two moving particles make angles of \(30^\circ \) and \(45^\circ \) with the \(x\)-axis as shown in the figure. The ratio of their respective velocities is:
362272
A body is thrown vertically upwards. If air resistance is to be taken into account, then the time during which the body rises is
1 Greater than the time of fall
2 Twice the time of fall
3 Equal to the time of fall
4 Less than the time of fall
Explanation:
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 is given by \(\frac{1}{2}(g - a)t_2^2 = \frac{{{u^2}}}{{2(g + a)}}\) \( \Rightarrow {t_2} = \frac{u}{{\sqrt {(g + a)(g - a)} }}\) \(\therefore {t_2} > {t_1}\) because \(\frac{1}{{g + a}} < \frac{1}{{g - a}}\)
PHXI03:MOTION IN A STRAIGHT LINE
362273
The graph shows position as a function of time for two trains running on parallel tracks. Which one of the following statements is true?
1 At time \({t_{B}}\), both trains have the same velocity.
2 Both trains have the same velocity at some time after \({t_{B}}\).
3 Both trains have the same velocity at some time before \({t_{B}}\).
4 Somewhere on the graph, both trains have the same acceleration.
Explanation:
Slope of curve \({B}\) and slope of curve \({A}\) is same before time \({T_{B}}\) only. Acceleration of \({A}\) is always zero, whereas that of \({B}\) is not zero.
PHXI03:MOTION IN A STRAIGHT LINE
362274
The displacement-time graphs of two moving particles make angles of \(30^\circ \) and \(45^\circ \) with the \(x\)-axis as shown in the figure. The ratio of their respective velocities is:
NEET Test Series from KOTA - 10 Papers In MS WORD
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PHXI03:MOTION IN A STRAIGHT LINE
362272
A body is thrown vertically upwards. If air resistance is to be taken into account, then the time during which the body rises is
1 Greater than the time of fall
2 Twice the time of fall
3 Equal to the time of fall
4 Less than the time of fall
Explanation:
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 is given by \(\frac{1}{2}(g - a)t_2^2 = \frac{{{u^2}}}{{2(g + a)}}\) \( \Rightarrow {t_2} = \frac{u}{{\sqrt {(g + a)(g - a)} }}\) \(\therefore {t_2} > {t_1}\) because \(\frac{1}{{g + a}} < \frac{1}{{g - a}}\)
PHXI03:MOTION IN A STRAIGHT LINE
362273
The graph shows position as a function of time for two trains running on parallel tracks. Which one of the following statements is true?
1 At time \({t_{B}}\), both trains have the same velocity.
2 Both trains have the same velocity at some time after \({t_{B}}\).
3 Both trains have the same velocity at some time before \({t_{B}}\).
4 Somewhere on the graph, both trains have the same acceleration.
Explanation:
Slope of curve \({B}\) and slope of curve \({A}\) is same before time \({T_{B}}\) only. Acceleration of \({A}\) is always zero, whereas that of \({B}\) is not zero.
PHXI03:MOTION IN A STRAIGHT LINE
362274
The displacement-time graphs of two moving particles make angles of \(30^\circ \) and \(45^\circ \) with the \(x\)-axis as shown in the figure. The ratio of their respective velocities is:
