All categories

3 years ago

Kiran runs along a straight road of length 150 m. After

Physics

1 answer:

Alexandra [31]3 years ago

4 0

Answer:

Explanation:

Speed and velocity are not the same thing, as I'm sure you have determined while in physics. To find the average speed, we add the total distance run by Kiran and divide that total number of meters by the number of seconds it took to do this (just because I am going to state the speed and velocity in terms of m/s as opposed to m/min). To find the average velocity, we add the displacements together and divide by the total time. First the average speed:

$s=\frac{150+150}{60}=\frac{300}{60}=5\frac{m}{s}$

Velocity has direction. If Kiran runs to the end of the road (which we will call positive) and then runs back to the start (that direction will be negative), then his displacement fits into the velocity equation as

$v=\frac{150+(-150)}{60}=0$ That means, even though he ran a lot and I'm sure he was very tired, his average velocity for the trip was 0 m/s. When velocity is 0, remember that that means that the total displacement was 0.

You might be interested in

A ball is projected into the air with 100 j of kinetic energy which is transformed to gravitational potential energy at the top

raketka [301]

<span>when it returns to its original level after encountering air resistance, its kinetic energy is decreased.
In fact, part of the energy has been dissipated due to the air resistance.

The mechanical energy of the ball as it starts the motion is:
</span> $E=K = 100 J$
<span>where K is the kinetic energy, and where there is no potential energy since we use the initial height of the ball as reference level.
If there is no air resistance, this total energy is conserved, therefore when the ball returns to its original height, the kinetic energy will still be 100 J. However, because of the presence of the air resistance, the total mechanical energy is not conserved, and part of the total energy of the ball has been dissipated through the air. Therefore, when the ball returns to its original level, the kinetic energy will be less than 100 J.</span>

3 0

3 years ago

Brainliest for correct answers :)

Nostrana [21]

Answer:

a. 1100 meters.

b. Between B and C

c.1. Between point D and E

c2. Between point D and E

d. 3.7 m/s.

Explanation:

The girl travels the distance of 1100 meters from starting to the end. There is no motion occurs between B and C due to no change of distance value from 200 meters. Between point D and E, the girls covers 500 meters long distance and also covers fastest distance between point D and E because between point D and E, the girl covers 500 meters distance in 30 seconds which is the highest of all. The average speed of the girls is 3.7 meter/seconds if we divide total distance i.e. 1100 meters by time which is 300 seconds.

6 0

3 years ago

A 100 kg box is suspended from two ropes. The "left rope makes an angle of 20" degrees with the vertical, and the right rope mak

GarryVolchara [31]

Explanation:

It is given that,

Mass of the box, m = 100 kg

Left rope makes an angle of 20 degrees with the vertical, and the right rope makes an angle of 40 degrees.

From the attached figure, the x and y component of forces is given by :

$T_{1x} =-T_1 cos (20)$

$T_{2x} = T_2 cos (40)$

$mg_x = 0$

$T_{1y} = T_1 sin (20)$

$T_{2y} = T_2 sin (40)$

$mg_y= -mg$

Let $R_x$ and $R_y$ is the resultant in x and y direction.

$R_x=-T_1 cos (20)+T_2 cos (40)+0$

$R_y=T_1 sin(20)+T_2 sin(40)-mg$

As the system is balanced the net force acting on it is 0. So,

$-T_1 cos (20)+T_2 cos (40)+0=0$ .............(1)

$T_1 sin(20)+T_2 sin(40)-100\times 9.8=0$ ..................(2)

On solving equation (1) and (2) we get:

$T_1=866.86\ N$ (tension on the left rope)

$T_2=1063.36\ N$ (tension on the right rope)

So, the tension on the right rope is 1063.36 N. Hence, this is the required solution.

7 0

3 years ago

Holly puts a box into the trunk of her car. Later, she drives around an unbanked curve that has a radius of 48 m. The speed of t

LiRa [457]

Answer:

The minimum coefficient of friction is 0.544

Solution:

As per the question:

Radius of the curve, R = 48 m

Speed of the car, v = 16 m/s

To calculate the minimum coefficient of static friction:

The centrifugal force on the box is in the outward direction and is given by:

$F_{c} = \frac{mv^{2}}{R}$

$f_{s} = \mu_{s}mg$

where

$\mu_{s}$ = coefficient of static friction

The net force on the box is zero, since, the box is stationary and is given by:

$F_{net} = f_{s} - F_{c}$

$0 = f_{s} - F_{c}$

$\mu_{s}mg = \frac{mv^{2}}{R}$

$\mu_{s} = \frac{v^{2}}{gR}$

$\mu_{s} = \frac{16^{2}}{9.8\times 48} = 0.544$

3 0

4 years ago

The metric system is a measurement system that is: only used by a few of the nations of the world. used exclusively in chemical

inysia [295]

Answer:

The metric system is the official system for all nations of the world.

Explanation:

To make measures, it is necessary to have a set of standardized magnitudes to compare things we want to measure. This set of standardized magnitudes is called a unit system.

The metric system is a decimalized system of measurement which has meters and grams as a basic measurement unit. The metric system is the most used in the world, and also, is the official system for all nations of the world.

7 0

3 years ago