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Champ Jee
Subject: Physics
, asked on 22/5/18
Q20.
Query: Position wrt time is given as t^3+3t^2+2t.
Why not +C??
Q.20. The acceleration of a particle varies with time t seconds according to the relation a = 6t + 6 m
${s}^{-2}$
. Find velocity and position as functions of time. It is given that the particle starts from origin at t = 0 with velocity 2 m
${s}^{-1}$
.
Answer
1
Champ Jee
Subject: Physics
, asked on 22/5/18
Q9. b part.
I will join the graph in answer.
Expert, can you explain at which point velocity i.e. speed will be maximum in graph and what's the reason?
Q.9. A stationary patticle of mass m = 1.5 kg is acted upon by a variable force. The variation of force with respect to displacetnent is plotted in Fig. 2.39.
a. Calculate the velocity acquired by the particle after getting displaced through 6 m.
b. What is the maximum speed attained by the particle and at what time is it attained?
Answer
2
Champ Jee
Subject: Physics
, asked on 22/5/18
Solve Q8. (b) part.
Q8. A car accelerates from rest with 2 ms
^{-2}
for 2 s and then decelerates constantly with 4 ms
^{-2}
for t
_{0}
_{ }
second to come to rest. The graph tor the motion is shown in Fig. 2.38.
Fig. 2.38
a. Find the maximum speed attained by the car.
h Find the value of t
_{0}
.
Answer
1
Champ Jee
Subject: Physics
, asked on 22/5/18
Ques. Sita is Driving along straight highway in her car. At time t=0, when sita is moving at 10 ms
^{-1}
in the positive x-direction, she passes a signpost at x=50m. Hence acceleration is function of time:
$a=2.0m{s}^{-2}-\left(\frac{1}{10}m{s}^{-3}\right)t$
a. Derive expressions for her velocity and position as functions of time.
b. At what time is her velocity greatest?
c. What is the maximum velocity?
d. Where is the car when it reaches the maximum velocity
Answer
1
Champ Jee
Subject: Physics
, asked on 22/5/18
Q. A particle moving rectilinearly at time t = 0 that its velocity
v
changes with time t according to the equation
v
=
${t}^{2}$
- t, where t is in seconds and
v
in m/s. Find the time interval for which the particle retards.
Answer
3
Champ Jee
Subject: Physics
, asked on 12/5/18
Q7,8. Ans: b,a :
For Problems 7 and 8
If a particle starts moving along a straight line withinitial velocity u under contact acceleration a, its displacement with time is given by the relation
$\mathrm{x}=\mathrm{ut}+\frac{1}{2}{\mathrm{at}}^{2}$
7. Differentiation of 'x' w.r.t. 't' will be
$\left(\mathrm{a}\right)\mathrm{y}=\frac{\mathrm{at}}{2}\left(\mathrm{b}\right)\mathrm{u}+\mathrm{at}\phantom{\rule{0ex}{0ex}}\left(\mathrm{c}\right)\mathrm{u}+2\mathrm{at}\left(\mathrm{d}\right)\frac{{\mathrm{ut}}^{2}}{2}+\frac{{\mathrm{at}}^{3}}{6}$
8. The concerned deviation of positon time realtion w.r.twill be. Differentiation of above result w.r.t. 't' will be
(a) a (b) u+a
(c) u (d) none
Answer
1
Gayatri Chaudhari
Subject: Physics
, asked on 3/3/18
Please ans this as soon as possible
Q.6. A body is freely falling under the action of gravity. It covers half the total distance in the last second of its fall. If it falls for n second, then value of n is
a. 2
b. 2 +
$\sqrt{2}$
c. 3
d. (4) 2 -
$\sqrt{2}$
Answer
1
Ankit Dhumale
Subject: Physics
, asked on 11/2/18
What is instantaneous velocity And where is it used or what are its applications
Answer
1
Hardik Mahto
Subject: Physics
, asked on 8/11/17
Question22
Q22. Which of the following statements is true about a particle of mass 1 Kg, projected from a horizontal surface at a speed of 20 m/s and an angle of 37° or sin–1(0.6) to the horizontal ? (g = 10 m/s
^{2}
)
(1) The maximum Power delivered by the gravitational force on the particle during it's projectile motion is 200 watts
(2) The maximum power delivered by the gravitational force is equal to 90 watts and occurs at the highest point of trajectory.
(3) The maximum Power delivered by the gravitational force is equal to 160 watts and occurs at the final instant just before the particle hits ground.
(4) The maximum Power delivered by the gravitational force on the particle by during it's projectile motion is 120 watts
Answer
1
Hardik Mahto
Subject: Physics
, asked on 8/11/17
Question 10
10.
Two particles are projected simultaneously at t = 0 from the top of a tower from a common projection point with a horizontal projection velocity of 24 m/s and a vertical projection velocity of 32 m/s respectively. Then after 2 secs, the distance between the two will be ?
(1) 112 m (2) 80 m
(3) 40 m (4) 20 m
Answer
1
Hrishikesh
Subject: Physics
, asked on 26/6/17
Can anybody please give me the all formulas of unit and measurment,projectile motion and laws of motion.
Answer
2
Avni
Subject: Physics
, asked on 15/7/16
2 cars,one travelling at 54km/hr and other at 90km/hr move towards each other along a narrow road. When they are 150m apart ,both the drivers applythe brakes simultaneously.The motion of each car is retarded at 3m/sec square and the collision is avoided. Find the distance between the cars when they come to rest
Answer
1
Sakshi Pankaj Kolhe
Subject: Physics
, asked on 2/10/20
Please solve my doubt...
Answer
1
Sakshi Pankaj Kolhe
Subject: Physics
, asked on 2/10/20
Please answer this question..
Answer
1
Sakshi Pankaj Kolhe
Subject: Physics
, asked on 2/10/20
Please solve this question...I don't know what the answer is
Answer
1
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Query: Position wrt time is given as t^3+3t^2+2t.

Why not +C??

Q.20. The acceleration of a particle varies with time t seconds according to the relation a = 6t + 6 m${s}^{-2}$. Find velocity and position as functions of time. It is given that the particle starts from origin at t = 0 with velocity 2 m ${s}^{-1}$.

I will join the graph in answer.

Expert, can you explain at which point velocity i.e. speed will be maximum in graph and what's the reason?

Q.9. A stationary patticle of mass m = 1.5 kg is acted upon by a variable force. The variation of force with respect to displacetnent is plotted in Fig. 2.39.

a. Calculate the velocity acquired by the particle after getting displaced through 6 m.

b. What is the maximum speed attained by the particle and at what time is it attained?

Q8. A car accelerates from rest with 2 ms

^{-2}for 2 s and then decelerates constantly with 4 ms^{-2}for t_{0}_{ }second to come to rest. The graph tor the motion is shown in Fig. 2.38.Fig. 2.38

a. Find the maximum speed attained by the car.

h Find the value of t

_{0}.^{-1}in the positive x-direction, she passes a signpost at x=50m. Hence acceleration is function of time:$a=2.0m{s}^{-2}-\left(\frac{1}{10}m{s}^{-3}\right)t$

a. Derive expressions for her velocity and position as functions of time.

b. At what time is her velocity greatest?

c. What is the maximum velocity?

d. Where is the car when it reaches the maximum velocity

Q. A particle moving rectilinearly at time t = 0 that its velocity

vchanges with time t according to the equationv= ${t}^{2}$- t, where t is in seconds andvin m/s. Find the time interval for which the particle retards.For Problems 7 and 8If a particle starts moving along a straight line withinitial velocity u under contact acceleration a, its displacement with time is given by the relation

$\mathrm{x}=\mathrm{ut}+\frac{1}{2}{\mathrm{at}}^{2}$

7. Differentiation of 'x' w.r.t. 't' will be

$\left(\mathrm{a}\right)\mathrm{y}=\frac{\mathrm{at}}{2}\left(\mathrm{b}\right)\mathrm{u}+\mathrm{at}\phantom{\rule{0ex}{0ex}}\left(\mathrm{c}\right)\mathrm{u}+2\mathrm{at}\left(\mathrm{d}\right)\frac{{\mathrm{ut}}^{2}}{2}+\frac{{\mathrm{at}}^{3}}{6}$

8. The concerned deviation of positon time realtion w.r.twill be. Differentiation of above result w.r.t. 't' will be

(a) a (b) u+a

(c) u (d) none

Q.6. A body is freely falling under the action of gravity. It covers half the total distance in the last second of its fall. If it falls for n second, then value of n is

a. 2

b. 2 + $\sqrt{2}$

c. 3

d. (4) 2 - $\sqrt{2}$

Q22. Which of the following statements is true about a particle of mass 1 Kg, projected from a horizontal surface at a speed of 20 m/s and an angle of 37° or sin–1(0.6) to the horizontal ? (g = 10 m/s

^{2})(1) The maximum Power delivered by the gravitational force on the particle during it's projectile motion is 200 watts

(2) The maximum power delivered by the gravitational force is equal to 90 watts and occurs at the highest point of trajectory.

(3) The maximum Power delivered by the gravitational force is equal to 160 watts and occurs at the final instant just before the particle hits ground.

(4) The maximum Power delivered by the gravitational force on the particle by during it's projectile motion is 120 watts

10. Two particles are projected simultaneously at t = 0 from the top of a tower from a common projection point with a horizontal projection velocity of 24 m/s and a vertical projection velocity of 32 m/s respectively. Then after 2 secs, the distance between the two will be ?

(1) 112 m (2) 80 m

(3) 40 m (4) 20 m