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Prithika
Subject: Science
, asked on 17/5/18
33
33.
A car accelerates from rest at a constant rate
$\alpha $
for some time, after which deaccelerates as a constant rate
$\beta $
to come to rest. If the total time elapsed is 1, the maximum velocity accquired to the car is given by
$\left(A\right)\left[\left(\alpha \beta \right)/\left(\alpha +\beta \right)\right]t\left(B\right)\left[\left(\alpha +\beta \right)/\left(\alpha \beta \right)\right]t\phantom{\rule{0ex}{0ex}}\left(C\right)\left[\left({\alpha}^{2}+{\beta}^{2}\right)/\left(\alpha \beta \right)\right]t\left(D\right)\left[\left({\alpha}^{2}-{\beta}^{2}\right)/\left(\alpha \beta \right)\right]t$
Answer
1
Prithika
Subject: Science
, asked on 17/5/18
Q.31. A person walks up a stationary escalator in 90 sec. If the escalator moves with the person just standing on it, it will take 1 minute to reach the top from ground. How much time it would take him to walk up the elevator?
(A) 24 sec
(B) 48 sec
(C) 36 sec
(D) 40 sec
Answer
1
Prithika
Subject: Science
, asked on 17/5/18
Solve this :
28. A particle is thrown vertically upward, its velocity at half of the height is 10m/s, then maximum height attained by it is : (g = 10m/s
^{2}
)
(a) 8m (b) 20m
(c) 10m (d) 16m
Answer
1
Prithika
Subject: Science
, asked on 17/5/18
Q.20. A body when projected vertically up, covers a total distance D during its time of flight. If there were no gravity, the distance covered by it during the same time is equal to
(A) 0
(B) D
(C) 2 D
(D) 4 D
Answer
1
Prithika
Subject: Science
, asked on 17/5/18
Q15
Q15. A car travelling at 36 km/hr due North tums West in 5 s under constant acceleration maintains the same speed. The acceleration of the car is
(A) 2
$\surd 2$
m/s
^{2 }
South-West (B) 10 m/s
^{2}
North-East
(C) 2
$\surd 2$
m/s
^{2}
South.East (D) 5 m/s
^{2}
North-West
Answer
1
Prithika
Subject: Science
, asked on 17/5/18
Q5
5. A motor car is going due north at a speed of 50 km/h. It makes of 90
^{o}
left turn without changeing the speed. the change in the velocity of the car is about.
(A) 50 km/h (B) 70 km/h fowards south west
(C) 70 km/h towards noth west (D) Zero.
Answer
1
Prithika
Subject: Science
, asked on 17/5/18
Q3
Answer
1
Prithika
Subject: Science
, asked on 17/5/18
Q.2. A particle moves in a straight line with a retardation proportional to its displacement. Its loss of kinetic energy for any displacement x is proportional to
(A) x
(B)
${x}^{2}$
(C) 1 / x
(D)1 /
${x}^{2}$
Answer
1
Devanshi Vora
Subject: Science
, asked on 17/5/18
apply ohms law to obtain the relationship for combined resistance when three resistors R1, R2,R3 are connected in a) series b) parallel
Answer
1
Devanshi Vora
Subject: Science
, asked on 17/5/18
List out any two advantages of connecting electrical appliances in parallel with the source in domestic circuit.
Answer
1
Rimas Musa
Subject: Science
, asked on 17/5/18
Q1 and Q2...please solve
$1.Threeresistorof2\Omega ,3\Omega and4\Omega areconnectedin\left(a\right)series\left(b\right)parallel.Findtheequivalentresis\mathrm{tan}ceineachcase.\phantom{\rule{0ex}{0ex}}2.Threeresistor,eachof2\Omega areconnectedtogethersothattheirtotalresis\mathrm{tan}ceis3\Omega .Drawadiagramtoshowthis\phantom{\rule{0ex}{0ex}}arrangementandcheckitbycalculation.$
Answer
4
Rimas Musa
Subject: Science
, asked on 17/5/18
three resistors 2? 3?and 4?are connected in (a) series (b) parallel. find the equivalent resistance in each case.
Answer
2
Siddharth
Subject: Science
, asked on 16/5/18
Solve this:
Answer
3
Siddharth
Subject: Science
, asked on 16/5/18
Ans 14
Q.14. A piece of wire is redrawn by pulling it until its length is doubled. Compare the new resistance with the original value?
Answer
2
Siddharth
Subject: Science
, asked on 16/5/18
Solve this:
Answer
1
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33.A car accelerates from rest at a constant rate $\alpha $ for some time, after which deaccelerates as a constant rate $\beta $ to come to rest. If the total time elapsed is 1, the maximum velocity accquired to the car is given by$\left(A\right)\left[\left(\alpha \beta \right)/\left(\alpha +\beta \right)\right]t\left(B\right)\left[\left(\alpha +\beta \right)/\left(\alpha \beta \right)\right]t\phantom{\rule{0ex}{0ex}}\left(C\right)\left[\left({\alpha}^{2}+{\beta}^{2}\right)/\left(\alpha \beta \right)\right]t\left(D\right)\left[\left({\alpha}^{2}-{\beta}^{2}\right)/\left(\alpha \beta \right)\right]t$

(A) 24 sec

(B) 48 sec

(C) 36 sec

(D) 40 sec

Solve this :28. A particle is thrown vertically upward, its velocity at half of the height is 10m/s, then maximum height attained by it is : (g = 10m/s

^{2})(a) 8m (b) 20m

(c) 10m (d) 16m

(A) 0

(B) D

(C) 2 D

(D) 4 D

Q15. A car travelling at 36 km/hr due North tums West in 5 s under constant acceleration maintains the same speed. The acceleration of the car is

(A) 2$\surd 2$ m/s

^{2 }South-West (B) 10 m/s^{2}North-East(C) 2$\surd 2$ m/s

^{2}South.East (D) 5 m/s^{2}North-West5. A motor car is going due north at a speed of 50 km/h. It makes of 90

^{o}left turn without changeing the speed. the change in the velocity of the car is about.(A) 50 km/h (B) 70 km/h fowards south west

(C) 70 km/h towards noth west (D) Zero.

(A) x

(B) ${x}^{2}$

(C) 1 / x

(D)1 / ${x}^{2}$

$1.Threeresistorof2\Omega ,3\Omega and4\Omega areconnectedin\left(a\right)series\left(b\right)parallel.Findtheequivalentresis\mathrm{tan}ceineachcase.\phantom{\rule{0ex}{0ex}}2.Threeresistor,eachof2\Omega areconnectedtogethersothattheirtotalresis\mathrm{tan}ceis3\Omega .Drawadiagramtoshowthis\phantom{\rule{0ex}{0ex}}arrangementandcheckitbycalculation.$

Q.14. A piece of wire is redrawn by pulling it until its length is doubled. Compare the new resistance with the original value?