Answer:
The average speed can be calculated as the quotient between the distance travelled and the time needed to travel that distance.
To go to the school, he travels 2.4 km in 0.6 hours, then here the average speed is:
s = (2.4km)/(0.6 hours) = 4 km/h
To return to his home, he travels 2.4km again, this time in only 0.4 hours, then here the average speed is:
s' = (2.4 km)/(0.4 hours) = 6 km/h.
Now, if we want the total average speed (of going and returning) we have that the total distance traveled is two times the distance between his home and school, and the total time is 0.6 hours plus 0.4 hours, then the average speed is:
S = (2*2.4 km)/(0.6 hours + 0.4 hours)
S = (4.8km)/(1 h) = 4.8 km/h
Answer:
We conclude that the kinetic energy of a 1.75 kg ball traveling at a speed of 54 m/s is 2551.5 J.
Explanation:
Given
To determine
Kinetic Energy (K.E) = ?
We know that a body can possess energy due to its movement — Kinetic Energy.
Kinetic Energy (K.E) can be determined using the formula

where
- K.E is the Kinetic Energy (J)
now substituting m = 1.75, and v = 54 in the formula



J
Therefore, the kinetic energy of a 1.75 kg ball traveling at a speed of 54 m/s is 2551.5 J.
Answer:
option A
Explanation:
given,
frequency is increased by 20%
we know,
...........(1)
where
x_n is the perpendicular distance between the point the interference pattern is obtained,
L is the distance between the center of the two point sources
and λ is the wavelength of light.
If the frequency is increased by 20%, then the number of nodal lines is increased by 20%.
From equation (1),we observe that the frequency is directly proportional to the number of nodal lines.
Hence, the correct answer is option A