362167
A body starting from rest moves with uniform acceleration. The distance covered by the body in time \(t\) is proportional to
1 \({t^2}\)
2 \({t^3}\)
3 \({t^{3/2}}\)
4 \(\sqrt t \)
Explanation:
Given : Initial velocity of a body \(u = 0\) Let \(s\) be the distance covered by a body in time \(t\) \(\therefore \;s = ut + \frac{1}{2}a{t^2}\;or\;s = \frac{1}{2}a{t^2}\) \( \Rightarrow s \propto {t^2}\)
PHXI03:MOTION IN A STRAIGHT LINE
362168
Which of the following four statements is false?
1 A body can have zero velocity and still be accelerated
2 A body can have a constant velocity and still have a varying speed
3 A body can have a constant speed and still have a varying velocity
4 The direction of the velocity of a body can change when its acceleration is constant
Explanation:
When a body is projected vertically upwards, at highest point its velocity is zero but still accelerated downwards. In uniform circular motion a body has constant speed and still have a varying velocity. In projectile motion direction of the velocity of a body changes, when its acceleration is constant. So correct option is (2)
PHXI03:MOTION IN A STRAIGHT LINE
362169
The acceleration time plot for a particle (starting from rest) moving on a straight line is shown in figure. For given time interval
1 The particle has turned around at \(t\) = 10 \(s\)
2 The particle has zero displacement
3 The average speed is same in both intervals 0 to 10 \(s\) and 10 \(s\) to 20 \(s\)
4 The particle has non- zero average acceleration
Explanation:
As the graph is symmetric about \(t\)-axis average value of \(a\) from \(0 \, s\) to \(20 \, s\) is zero. The average speed is same from \(0 \, s\) to \(10 \, s\) and from \(10 \, s\) to \(20 \,s\) since the area of triangles are same. From \(0 \, s\) to \(10 \, s\) the particle is in acceleration and \(10 \,s\) and \(20 \, s\) the particle is in deceleration but it is moving in same direction, so displacement is non zero.
PHXI03:MOTION IN A STRAIGHT LINE
362170
The velocity of a particle moving in the positive direction of \(x = \) axis varies as \(v = 5\sqrt x \). Assuming that at \(t = 0\), particle was at \(x = 0\). What is the acceleration of the particle?
1 \(12.5\,m/{s^2}\)
2 \(7.5\,m/{s^2}\)
3 \(5\,m/{s^2}\)
4 \(2.5\,m/{s^2}\)
Explanation:
\({v^2} = 25 \times \;\) comparing with \({v^2} = 2as\), we have, \(a = 12.5\,m/{s^2}\)
362167
A body starting from rest moves with uniform acceleration. The distance covered by the body in time \(t\) is proportional to
1 \({t^2}\)
2 \({t^3}\)
3 \({t^{3/2}}\)
4 \(\sqrt t \)
Explanation:
Given : Initial velocity of a body \(u = 0\) Let \(s\) be the distance covered by a body in time \(t\) \(\therefore \;s = ut + \frac{1}{2}a{t^2}\;or\;s = \frac{1}{2}a{t^2}\) \( \Rightarrow s \propto {t^2}\)
PHXI03:MOTION IN A STRAIGHT LINE
362168
Which of the following four statements is false?
1 A body can have zero velocity and still be accelerated
2 A body can have a constant velocity and still have a varying speed
3 A body can have a constant speed and still have a varying velocity
4 The direction of the velocity of a body can change when its acceleration is constant
Explanation:
When a body is projected vertically upwards, at highest point its velocity is zero but still accelerated downwards. In uniform circular motion a body has constant speed and still have a varying velocity. In projectile motion direction of the velocity of a body changes, when its acceleration is constant. So correct option is (2)
PHXI03:MOTION IN A STRAIGHT LINE
362169
The acceleration time plot for a particle (starting from rest) moving on a straight line is shown in figure. For given time interval
1 The particle has turned around at \(t\) = 10 \(s\)
2 The particle has zero displacement
3 The average speed is same in both intervals 0 to 10 \(s\) and 10 \(s\) to 20 \(s\)
4 The particle has non- zero average acceleration
Explanation:
As the graph is symmetric about \(t\)-axis average value of \(a\) from \(0 \, s\) to \(20 \, s\) is zero. The average speed is same from \(0 \, s\) to \(10 \, s\) and from \(10 \, s\) to \(20 \,s\) since the area of triangles are same. From \(0 \, s\) to \(10 \, s\) the particle is in acceleration and \(10 \,s\) and \(20 \, s\) the particle is in deceleration but it is moving in same direction, so displacement is non zero.
PHXI03:MOTION IN A STRAIGHT LINE
362170
The velocity of a particle moving in the positive direction of \(x = \) axis varies as \(v = 5\sqrt x \). Assuming that at \(t = 0\), particle was at \(x = 0\). What is the acceleration of the particle?
1 \(12.5\,m/{s^2}\)
2 \(7.5\,m/{s^2}\)
3 \(5\,m/{s^2}\)
4 \(2.5\,m/{s^2}\)
Explanation:
\({v^2} = 25 \times \;\) comparing with \({v^2} = 2as\), we have, \(a = 12.5\,m/{s^2}\)
362167
A body starting from rest moves with uniform acceleration. The distance covered by the body in time \(t\) is proportional to
1 \({t^2}\)
2 \({t^3}\)
3 \({t^{3/2}}\)
4 \(\sqrt t \)
Explanation:
Given : Initial velocity of a body \(u = 0\) Let \(s\) be the distance covered by a body in time \(t\) \(\therefore \;s = ut + \frac{1}{2}a{t^2}\;or\;s = \frac{1}{2}a{t^2}\) \( \Rightarrow s \propto {t^2}\)
PHXI03:MOTION IN A STRAIGHT LINE
362168
Which of the following four statements is false?
1 A body can have zero velocity and still be accelerated
2 A body can have a constant velocity and still have a varying speed
3 A body can have a constant speed and still have a varying velocity
4 The direction of the velocity of a body can change when its acceleration is constant
Explanation:
When a body is projected vertically upwards, at highest point its velocity is zero but still accelerated downwards. In uniform circular motion a body has constant speed and still have a varying velocity. In projectile motion direction of the velocity of a body changes, when its acceleration is constant. So correct option is (2)
PHXI03:MOTION IN A STRAIGHT LINE
362169
The acceleration time plot for a particle (starting from rest) moving on a straight line is shown in figure. For given time interval
1 The particle has turned around at \(t\) = 10 \(s\)
2 The particle has zero displacement
3 The average speed is same in both intervals 0 to 10 \(s\) and 10 \(s\) to 20 \(s\)
4 The particle has non- zero average acceleration
Explanation:
As the graph is symmetric about \(t\)-axis average value of \(a\) from \(0 \, s\) to \(20 \, s\) is zero. The average speed is same from \(0 \, s\) to \(10 \, s\) and from \(10 \, s\) to \(20 \,s\) since the area of triangles are same. From \(0 \, s\) to \(10 \, s\) the particle is in acceleration and \(10 \,s\) and \(20 \, s\) the particle is in deceleration but it is moving in same direction, so displacement is non zero.
PHXI03:MOTION IN A STRAIGHT LINE
362170
The velocity of a particle moving in the positive direction of \(x = \) axis varies as \(v = 5\sqrt x \). Assuming that at \(t = 0\), particle was at \(x = 0\). What is the acceleration of the particle?
1 \(12.5\,m/{s^2}\)
2 \(7.5\,m/{s^2}\)
3 \(5\,m/{s^2}\)
4 \(2.5\,m/{s^2}\)
Explanation:
\({v^2} = 25 \times \;\) comparing with \({v^2} = 2as\), we have, \(a = 12.5\,m/{s^2}\)
362167
A body starting from rest moves with uniform acceleration. The distance covered by the body in time \(t\) is proportional to
1 \({t^2}\)
2 \({t^3}\)
3 \({t^{3/2}}\)
4 \(\sqrt t \)
Explanation:
Given : Initial velocity of a body \(u = 0\) Let \(s\) be the distance covered by a body in time \(t\) \(\therefore \;s = ut + \frac{1}{2}a{t^2}\;or\;s = \frac{1}{2}a{t^2}\) \( \Rightarrow s \propto {t^2}\)
PHXI03:MOTION IN A STRAIGHT LINE
362168
Which of the following four statements is false?
1 A body can have zero velocity and still be accelerated
2 A body can have a constant velocity and still have a varying speed
3 A body can have a constant speed and still have a varying velocity
4 The direction of the velocity of a body can change when its acceleration is constant
Explanation:
When a body is projected vertically upwards, at highest point its velocity is zero but still accelerated downwards. In uniform circular motion a body has constant speed and still have a varying velocity. In projectile motion direction of the velocity of a body changes, when its acceleration is constant. So correct option is (2)
PHXI03:MOTION IN A STRAIGHT LINE
362169
The acceleration time plot for a particle (starting from rest) moving on a straight line is shown in figure. For given time interval
1 The particle has turned around at \(t\) = 10 \(s\)
2 The particle has zero displacement
3 The average speed is same in both intervals 0 to 10 \(s\) and 10 \(s\) to 20 \(s\)
4 The particle has non- zero average acceleration
Explanation:
As the graph is symmetric about \(t\)-axis average value of \(a\) from \(0 \, s\) to \(20 \, s\) is zero. The average speed is same from \(0 \, s\) to \(10 \, s\) and from \(10 \, s\) to \(20 \,s\) since the area of triangles are same. From \(0 \, s\) to \(10 \, s\) the particle is in acceleration and \(10 \,s\) and \(20 \, s\) the particle is in deceleration but it is moving in same direction, so displacement is non zero.
PHXI03:MOTION IN A STRAIGHT LINE
362170
The velocity of a particle moving in the positive direction of \(x = \) axis varies as \(v = 5\sqrt x \). Assuming that at \(t = 0\), particle was at \(x = 0\). What is the acceleration of the particle?
1 \(12.5\,m/{s^2}\)
2 \(7.5\,m/{s^2}\)
3 \(5\,m/{s^2}\)
4 \(2.5\,m/{s^2}\)
Explanation:
\({v^2} = 25 \times \;\) comparing with \({v^2} = 2as\), we have, \(a = 12.5\,m/{s^2}\)
