The density decreases and convection causes the hot air particles to rise! BRANLIEST
Answer:
d = 375 m
Explanation:
The speed of sound is constant in any medium, therefore we can use the uniform motion relationships
v = x / t
x = v t
In this case it indicates that the time since the sound is emitted and received is t = 0.50 s, in this time the sound traveled a round trip distance
x = 2d
2d = v t
d = v t/2
let's calculate
d = 1500 0.5 / 2
d = 375 m
Answer:
, charges are both positive or both negative
Explanation:
The electrostatic force between the two spheres is given by

where
k is the Coulomb's constant
q1 and q2 are the charges on the two spheres
r is the distance between the centres of the two spheres
In this problem, we have
is the force
is the distance between the spheres
because the two spheres have identical charge
Solving the formula for q, we find

And the two charges have the same sign (so, both positive or both negative), since the sign of the force is positive (+0.30 N), so it is a repulsive force.
Answer:
Car A has a velocity of 40 km/hr west.
Explanation:
The velocity of an object is a vector quantity. It has both magnitudes as well as direction.
Arrows are used to show direction.
Car A is moving towards west. Car B is moving towards east-south direction. Car C is moving towards South direction. Car E is moving towards North direction.
So, the correct option is (a) i.e. Car A has a velocity of 40 km/hr west.