Answer:
Speed of the ball relative to the boys: 25 km/h
Speed of the ball relative to a stationary observer: 35 km/h
Explanation:
The RV is travelling at a velocity of
Here we have taken the direction of motion of the RV as positive direction.
The boy sitting near the driver throws the ball back with speed of 25 km/h, so the velocity of the ball in the reference frame of the RV is
with negative sign since it is travelling in the opposite direction relative to the RV. Therefore, this is the velocity measured by every observer in the reference frame of the RV: so the speed measured by the boys is
v = 25 km/h
Instead, a stationary observer outside the RV measures a velocity of the ball given by the algebraic sum of the two velocities:
v = +60 km/h + (-25 km/h) = +35 km/h
So, he/she measures a speed of 35 km/h.
Answer:
<em>Asha traveled a distance of 50 m</em>
<em>The displacement is 20 m north.</em>
Explanation:
<u>Distance and Displacement
</u>
A moving object constantly travels for some distances at defined periods of time. The total moved distance is the sum of each individual distance the object traveled. It can be written as:
dtotal=d1+d2+d3+...+dn
This sum is obtained independently of the direction the object moves.
The displacement only takes into consideration the initial and final positions of the object while moving. The displacement, unlike distance, is a vectorial magnitude and can even have magnitude zero if the object starts and ends the movement at the same point.
Asha walks 15 m west, 20 m north, and 15 m east. The total distance is
dt=15 m + 20 m + 15 m = 50 m
Asha traveled a distance of 50 m
Note the final position is 20 m above the initial position since she goes 15 m west and 15 m east. Thus the displacement is 20 m north.
Answer:
the book is exerting a force of 15N on the table as we know that every action has an equal but opposite reaction so there must be a force acting on it in the opposite direction the other force normal force or we can say it perpendicular force that is defined as a contact force perpendicular to the contact surface that prevent two objects from passing over one another
Explanation:
i hope it will help you
Answer:
The magnitude of the applied torque is 
(e) is correct option.
Explanation:
Given that,
Mass of object = 3 kg
Radius of gyration = 0.2 m
Angular acceleration = 0.5 rad/s²
We need to calculate the applied torque
Using formula of torque
Here, I = mk²
Put the value into the formula
Hence, The magnitude of the applied torque is
Answer:
The third lowest frequency is 1489.27 Hz.
Explanation:
Given that,
Distance of person from one speaker= 4.50 m
Distance of person from the other = 3.80 m
The longest wavelength is the shortest frequency.
We need to calculate the difference between the speakers
The difference between the speakers d= 4.50-3.80 =0.7 m
We know that,
The longest wavelength is such that one wavelength
So, The third longest wavelength is
Put the value of d
We need to calculate the lowest frequency
Using formula of frequency
Hence, The third lowest frequency is 1489.27 Hz.
