A boy standing at the top of a tower of \(20\) m height drops a stone. Assuming \(g=10\) m/s2, the velocity with which it hits the ground will be:
1. \(20\) m/s
2. \(40\) m/s
3. \(5\) m/s
4. \(10\) m/s
If a body is thrown up with the velocity of \(15\) m/s, then the maximum height attained by the body is: (assume \(g = 10\) m/s2)
1. \(11.25\) m
2. \(16.2\) m
3. \(24.5\) m
4. \(7.62\) m
A body starts to fall freely under gravity. The distances covered by it in the first, second and third second will be in the ratio:
1. \(1:3:5\)
2. \(1:2:3\)
3. \(1:4:9\)
4. \(1:5:6\)
A body is thrown upwards and reaches its maximum height. At that position:
1. | its velocity is zero and its acceleration is also zero. |
2. | its velocity is zero but its acceleration is maximum. |
3. | its acceleration is minimum. |
4. | its velocity is zero and its acceleration is the acceleration due to gravity. |
A ball is thrown vertically downwards with a velocity of \(20\) m/s from the top of a tower. It hits the ground after some time with the velocity of \(80\) m/s . The height of the tower is: (assuming \(g = 10~\text{m/s}^2)\)
1. | \(340\) m | 2. | \(320\) m |
3. | \(300\) m | 4. | \(360\) m |
A stone falls freely under gravity. It covers distances \(h_1,~h_2\) and \(h_3\) in the first \(5\) seconds, the next \(5\) seconds and the next \(5\) seconds respectively. The relation between \(h_1,~h_2\) and \(h_3\) is:
1. | \(h_1=\frac{h_2}{3}=\frac{h_3}{5}\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \) |
2. | \(h_2=3h_1\) and \(h_3=3h_2\) |
3. | \(h_1=h_2=h_3\) |
4. | \(h_1=2h_2=3h_3\) |
A body is thrown vertically up from the ground. It reaches a maximum height of \(100\) m in \(5\) s. After what time will it reach the ground from the position of maximum height?
1. \(1.2\) s
2. \(5\) s
3. \(10\) s
4. \(25\) s
A car travelling at a speed of \(30\) km/h is brought to rest at a distance of \(8\) m by applying brakes. If the same car is moving at a speed of \(60\) km/h, then it can be brought to rest with the same brakes in:
1. \(64\) m
2. \(32\) m
3. \(16\) m
4. \(4\) m
A body starting from rest moves with uniform acceleration on a horizontal surface. The body covers \(3\) consecutive equal distances from the beginning in time \(t_1, t_2,\text{and}~t_3\) seconds. The ratio of \(t_1:t_2:t_3\) is:
1. \(1:2:3\)
2. \(1:\sqrt{2}:\sqrt{3}\)
3. \(1:\left(\sqrt{2}-1\right):\left(\sqrt{3}-\sqrt{2}\right)\)
4. \(\sqrt{3}:\sqrt{2}:1\)
A particle moves in a straight line with a constant acceleration. It changes its velocity from \(10\) ms-1 to \(20\) ms-1 while covering a distance of \(135\) m in \(t\) seconds. The value of \(t\) is:
1. | \(10\) | 2. | \(1.8\) |
3. | \(12\) | 4. | \(9\) |