Motion in a Straight Line Test 4

Explanation:To describe motion along a straight line, we can choose an axis, say X-axis, so that it coincides with the path of the object. We then measure the position of the object with reference to a conveniently chosen origin, say O, Positions to the right of O are taken as positive and to the left of O, as negative.

Explanation:Position-time graph of horizontal straight line parallel to time axis represents that the position of the body does not changes with the passage of time. So it represents the rest state of motion.It means velocity of object is zero.

Explanation:To describe motion along a straight line, we can choose an axis, say X-axis, so that it coincides with the path of the object. We then measure the position of the object with reference to a conveniently chosen origin, say O,  Positions to the right of O are taken as positive and to the left of O, as negative.

Explanation:

Acceleration is the rate of change of velocity with time.It is a vector quantity.

Average acceleration is the change in velocity per unit time over an interval of time.

Let initial velocity at time interval t​​​​​​₁ is v​​​​​​₁ and final velocity at time interval t​​​​​₂ is v​​​​​​₂ Then

Explanation:Path length is defined as the total length of the path traversed by an object.

Unlike displacement, which is the total distance an object travels from a starting point, path length is the total distance travelled, regardless of where it travelled.

Explanation:When velocity – time graph is plotted for an object moving with uniform acceleration, the slope of the graph is a straight line. 

Explanation:

Initial velocity u = 20.0 m/s

At maximum height stone ll  be stopped, 

So final velocity v = 0 m/s

Acceleration due to gravity a = g =

-9.8 m/s^{​​​​​​2} (-ve Because it is in opposite direction of motion)

Let maximum height = s

We know,

Explanation:Path length has no particular direction and it depends upon the path chosen to reach the destination where displacement of the destination is absolute no matter what path is used to get there. So it is scaler.

Explanation:The area under the velocity-time curve between times t₁​​​and t​​​​​​₂ is equal to the displacement of the object during that interval of time.

Explanation:

Average velocity can be defined as the displacement divided by the time.

Total displacement d = 18 m

Time taken t = 1 s

Again to reach same level from where it has been thrown it have to cover same distance downward.

For this initial velocity u = 0 

s = 20.4 m

a = 9.8 m/s^{​​​​​​2} (+be because motion is in same direction).

So,

Explanation:Kinematics is a branch of classical mechanics that describes the motion of points, bodies (objects), and systems of bodies (groups of objects) without considering the mass of each or the forces that caused the motion.

Explanation:Point object is an expression used in kinematics branch of physics: it is an object whose dimensions are ignored or neglected while considering its motion.The size of a carriage is very small as compared to the distance between two stations. Therefore, the carriage can be treated as a point sized object.

Explanation:Motion is a change in position of an object with time. In order to specify position, we need to use a reference point and a set of axes. It is convenient to choose a rectangular coordinate system consisting of three mutually perpenducular axes, labelled X-, Y-, and Z- axes.

The point of intersection of these three axes is called origin (O) and serves as the reference point. The coordinates (x, y. z) of an object describe the position of the object with respect to this coordinate system.

To measure time, we position a clock in this system. This coordinate system along with a clock constitutes a frame of reference.

Explanation:

Initial velocity u = 0

Acceleration a = 10.0 m/s^{​​​​​​2}

Distance covered s = 400 m

Time taken t = ?

We know

Explanation:

Initial velocity u = 20.0 m/s

At maximum height it ll stop

So final velocity v = 0 m/s

Acceleration due to gravity g = 9.8 m/s^{​​​​​​2}

Time taken to reach maximum height = t

We know

v = u + at

Explanation:Displacement vector is a vector which gives the position of a point with reference to a point other than the origin of the coordinate system.

Explanation:A speedometer or a speed meter is a gauge that measures and displays the instantaneous speed of a vehicle. Now universally fitted to motor vehicles, they started to be available as options in the 1900s, and as standard equipment from about 1910 onwards.

Speedometers for other vehicles have specific names and use other means of sensing speed. For a boat, this is a pit log. For an aircraft, this is an airspeed indicator.

Charles Babbage is credited with creating an early type of a speedometer, which were usually fitted to locomotives.

Explanation:Rectilinear motion is another name for straight-line motion. This type of motion describes the movement of a particle or a body. A body is said to experience rectilinear motion if any two particles of the body travel the same distance along two parallel straight lines.

Explanation:Uniform motion is the kind of motion in which a body covers equal displacement in equal intervals of time. It does not matter how small the time intervals are, as long as the displacements covered are equal.

If a body is involved in rectilinear motion and the motion is uniform, then the acceleration of the body must be zero.

Explanation:

Initial velocity u = 2 m/s

final velocity = v m/s

Time duration = final time - initial time = 2-0 = 2 s

acceleration a = 2 m/s^{​​​​​​2}

We know,

v = u + at

=> v = 2+2x2

=> v = 6 m/s