Answer:
a. 30 N / m
b. 9.0 N
Explanation:
Given that
Unstretched length of the spring, 
= 20.0cm = 0.2m
a) When the mass of 4.5N is hanging from the second spring, then extended length Is
= 35.0cm = 0.35m
So, the change in spring length when mass hangs is
= (0.35 - 0.20) m
= 0.15m
As spring are identical
Let us assume that the spring constant be "k", so at equilibrium
Restoring Force on spring = Block weightage
kx = W = 4.50
= 30 N / m
b) Now for the third spring, stretched the length of spring is
= 50cm = 0.5m
So, the change in spring length is
= (0.5-0.20)m
= 0.30m
At equilibrium,
Restoring Force on spring = Block weightage
Now using all mentioned and computed values in above,
= 30(0.3)
= 9.0 N
<span>14 m/s
Assuming that all of the energy stored in the spring is transferred to dart, we have 2 equations to take into consideration.
1. How much energy is stored in the spring?
2. How fast will the dart travel with that amount of energy.
As for the energy stored, that's a simple matter of multiplication. So:
20 N * 0.05 m = 1 Nm = 1 J
For the second part, the energy of a moving object is expressed as
KE = 0.5 mv^2
where
KE = Kinetic energy
m = mass
v = velocity
Since we now know the energy (in Joules) and mass of the dart, we can substitute the known values and solve for v. So
KE = 0.5 mv^2
1 J = 0.5 0.010 kg * v^2
1 kg*m^2/s^2 = 0.005 kg * v^2
200 m^2/s^2 = v^2
14.14213562 m/s = v
So the dart will have a velocity of 14 m/s after rounding to 2 significant figures.</span>
Answer:
Explanation:
Small grains are negatively charged by the wind while big grains is positively charged and remains at the ground . This process creates an electric field due to the presence of oppositely charged particles.
When ever electric field exists it is directed from a positive charge to a negative charge so the here electric field is towards an upwards direction.
Ok the velocity of an object in free fall is given by the equation :
v=v0-gt, where v0 is the original velocity, g is the gravitational constant (9.8 m/s^2) and t is the time.
so, we substitute values into this equation. v=35.8-9.8*2.5; v=11.3 m/s
Answer:
red has a longer wavelength than yellow. Yellow has a longer wavelength than green.
Explanation
in the visible spectrum a color with high frequency contains shorter wavelength.In this case red color has high wavelength followed by yellow followed by green,blue and violet.
