In order to completely describe a velocity,
you need a speed and a direction.
Answer:
The frictional force between two bodies depends mainly on three factors: (I) the adhesion between body surfaces (ii) roughness of the surface (iii) deformation of bodies
Answer:
Approximately
(assuming that the projectile was launched at angle of
above the horizon.)
Explanation:
Initial vertical component of velocity:
.
The question assumed that there is no drag on this projectile. Additionally, the altitude of this projectile just before landing
is the same as the altitude
at which this projectile was launched:
.
Hence, the initial vertical velocity of this projectile would be the exact opposite of the vertical velocity of this projectile right before landing. Since the initial vertical velocity is
(upwards,) the vertical velocity right before landing would be
(downwards.) The change in vertical velocity is:
.
Since there is no drag on this projectile, the vertical acceleration of this projectile would be
. In other words,
.
Hence, the time it takes to achieve a (vertical) velocity change of
would be:
.
Hence, this projectile would be in the air for approximately
.
Answer: Negatively charged particles are repelled by other negatively charged particles
Explanation:
Answer: Phillipe wins the race
Explanation:
Given
Length of track=20 m
Velocity of Phillippe=2 m/s w.r.t sidewalk
Velocity of sidewalk=1.5 m/s
Rena velocity=2 m/s
Therefore absolute velocity of P is 2+1.5=3.5 m/s
Time taken by phillippe 
=5.714+10=15.714 s
Time taken by rena

as the time taken by phillippe is less than rena therefore Phillippe wins the race.