◈ As per newton's second law of motion, Force is defined as the product of mass and acceleration
Mathematically,
Unit of mass : kg
Unit of acceleration : m/s²
Therefore,
Unit of force ➠ <u>kg m/s²</u>
SI unit : <u>N (newton)</u> or <u>kg m/s²</u>
Answer:
0.334 m
Explanation:
The magnetic field due to current in a straight thin wire, , is given by
where is the permeability of free spave with value
and
is the distance from the wire.
Substituting the values from the question,
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.