1. Change in position of a body from the initial to the final point is called:
The total length covered by the moving body without mentioning the direction of motion from the initial to the final position is called distance. In fig. 16 km and 24 km are distances while the shortest distance 6 km is Displacement
2. Motion of a screw of the rotating fan is
The motion of the body around fixed axes that passes through the body itself is called spin or rotatory motion. As every point (its Blade, screw, etc.) of the fan moves in a circle around a fixed axis so it is a Rotatory motion.
3. For a car in motion for some time
The total length covered by the moving body without mentioning the direction of motion from the initial to the final position is called distance. The Distance may be different depending on the path followed as shown in Fig. The shortest distance is equal to Displacement The distance can't be smaller than the Displacement
4. A girl walks 3 km towards the west and 4 km towards the south. What are her total distance and displacement respectively?
Distance = AB + BC = 3 km + 4 km = 7 km, while Displacement = `\sqrt {(3 km)²+ (4 km)²}` Displacement = `\sqrt {9 km²+ 16 km²}` Displacement = `\sqrt {25 km∆}` Displacement = 5 km
5. A rider is training a horse. The horse moves 60 meters towards the right in 3 seconds. Then it turns back and travels 30 metres in 2 seconds. Find its average velocity?
Average velocity is the total displacement covered in total time `\∆ vec v` = `\frac {vec d}{t}` Here displacement = 60 m - 30 m = 30 m, Time elapsed = 3 s + 2 s = 5 s. Average Velocity = 30 m / 5 s = 6 m/s
6. If a cyclist has an acceleration of 2m/s for 5 seconds, the change in velocity of the cyclist is
We know that `\vec a` = `\frac {∆vec v}{∆t}`, Acceleration = a = 3 m/s² and Time elapsed = t = 5 s. Solution: From the above equation `\∆ vec v` = `\vec a` x ∆t = 3 m/s² x 5 s = 15 m/s
Data: vi = 10 m/s, a = 2 m/s² and Time elapsed = ∆t = 10 s Solution: From the above equation vf = a x ∆t + vi vf = (2 m/s² x 10 s) + 10 m/s = 30 m/s
Increasing Velocity: The displacement changes non-linearly with time (curving up). The slope is increasing therefore the object is increasing its velocity.
When a ball is thrown straight up, Its acceleration gradually decreases due to gravitational full and at the top of its path, it comes to rest. so its velocity and acceleration become zero.
The gradient (slope) on the distance-time graph is numerically equal to the speed v = s/t
On a speed-time graph, the area under a line is numerically equal to the distance.
The physical quantities which are completely specified by magnitude with the suitable units and particular directions are called “Vector” quantities. Gravitational acceleration is a vector quantity having both magnitudes with suitable units and directions.
We know that `\vec a` = `\frac {∆vec v}{∆t}`, Acceleration = a = 3 m/s² and Time elapsed = t = 5 s. Solution: From the above equation `\∆ vec v` = `\vec a` x ∆t = 3 m/s² x 5 s = 15 m/s
7. A car is moving with a velocity of 10 m/s. If it has an acceleration of 2 m/s for 10 seconds. What is the final velocity of the car?
Data: vi = 10 m/s, a = 2 m/s² and Time elapsed = ∆t = 10 s Solution: From the above equation vf = a x ∆t + vi vf = (2 m/s² x 10 s) + 10 m/s = 30 m/s
8. When the slope of a body's displacement-time graph increases, the body is moving with:
Increasing Velocity: The displacement changes non-linearly with time (curving up). The slope is increasing therefore the object is increasing its velocity.
9. A ball is thrown straight up, what is its acceleration at the top of its path?
²
When a ball is thrown straight up, Its acceleration gradually decreases due to gravitational full and at the top of its path, it comes to rest. so its velocity and acceleration become zero.
10. Slope of the distance-time graph is:
The gradient (slope) on the distance-time graph is numerically equal to the speed v = s/t
11. Area under the speed-time graph is equal to -----------of moving body:
On a speed-time graph, the area under a line is numerically equal to the distance.
12. Which of the following is a vector quantity?
The physical quantities which are completely specified by magnitude with the suitable units and particular directions are called “Vector” quantities. Gravitational acceleration is a vector quantity having both magnitudes with suitable units and directions.
13. Ball thrown freely from a tower reaches the ground in 4s, the height of the tower is about
... Answer is C. 80m
-----------------
14. Which of the following distance time graphs represents the increasing speed of a car?
Increasing Speed: The distance changes non-linearly with time (curving up). The slope is increasing therefore the object is increasing its speed.
************************************
Shortcut Links For
1. Website for School and College Level Physics 2. Website for School and College Level Mathematics 3. Website for Single National Curriculum Pakistan - All Subjects Notes © 2020-21 Academic Skills and Knowledge (ASK) Note: Write to me in the comments box below for any query and also Share this information with your class-fellows and friends. |
0 Comments
If you have any QUESTIONs or DOUBTS, Please! let me know in the comments box or by WhatsApp 03339719149