To get to school a girl walks 1 km North in 15 minutes she th
en walks 200metere Southwest in 160 second find her average velocity
All angles are measured CW from +y-axis.
V1 = 1000m/900s = 1.11 m/s[0o].
V2 = 200m/160s = 1.25 m/s[225o].
V = 1.11[0o] + 1.25[225o].
V = (1.11*sin0+1.25*sin225) + (1.11*cos0+1.25*cos225)I,
V = -0.884 + 0.226i = 0.912m/s[-90o] = 0.912m/s[270o] CW.
To find the average velocity of the girl, we need to calculate the total displacement and the total time taken.
First, let's convert the given distances and time into a consistent unit. We know that 1 km is equal to 1000 meters, and there are 60 seconds in a minute.
The girl walks 1 km North, which is equivalent to 1,000 meters North. She does this in 15 minutes, which is equal to 15 * 60 = 900 seconds.
The girl then walks 200 meters Southwest in 160 seconds.
To find the total displacement, we need to add the vectors of the two movements. Since the girl walked North and Southwest, we can represent the North direction as positive and the Southwest direction as negative.
The displacement in the North direction is 1,000 meters North, and the displacement in the Southwest direction is 200 meters Southwest, which can be represented as -200 meters.
So, the total displacement is 1,000 meters North + (-200) meters Southwest = 800 meters North.
To find the total time taken, we need to add the times of the two movements. The girl took 900 seconds for the first movement and 160 seconds for the second movement.
So, the total time taken is 900 seconds + 160 seconds = 1,060 seconds.
Now we can calculate the average velocity using the formula: average velocity = displacement / time.
The average velocity = 800 meters North / 1,060 seconds = 0.7547 meters/second (rounded to four decimal places).
Therefore, the girl's average velocity is approximately 0.7547 meters/second.
Answer
graphh is important for these questio
Well, let's break it down. In the first part, the girl walks 1 km north in 15 minutes. That's some impressive exercise! Now, to calculate her average velocity, we need to divide the distance traveled by the time taken. Since 1 kilometer is equal to 1000 meters, her distance is 1000 meters. And since 15 minutes is equal to 900 seconds, her time is 900 seconds. So, her average velocity for the first part is 1000 meters divided by 900 seconds. Moving on to the second part, the girl walks 200 meters southwest in 160 seconds. Now, for this part, we don't need to convert anything as the units are already in meters and seconds. So, her average velocity for the second part is 200 meters divided by 160 seconds. Finally, to find her overall average velocity, we can add the two average velocities together and divide by 2. And voila, there you have it! Her average velocity.
well, velocity is a vector so we need to find her displacement vector from start to finish.
1 km in y direction
then .2 cos 45 in negative y direction and .2 sin 45 in negative x direction
so in the end
y = 1 - .141 = .858 km north
x = -.141 or .141 km west
distance from start =sqrt(.858^2+.141^2) = sqrt(.736+.020) =.869 km
time = .25 hr + 160/3600 hr = .25 + .04 = .29 hr
so .869 km/.29 hr = 3 km/hour
direction = tan^-1 (.141/.858) degrees west of north
or 9.23 deg west of north which is 360-9.23 =351 on your compass if all directions given are magnetic not true.