Answer:
if you stretch a spring with k = 2, with a force of 4N, the extension will be 2m. the work done by us here is 4x2=8J. in other words, the energy transferred to the spring is 8J. but, the stored energy in the spring equals 1/2x2x2^2=4J (which is half of the work done by us in stretching it).
Answer:
v = √(25/m)
Explanation:
KE = ½mv²
v = √(2KE/m)
We know the kinetic energy, but not the mass
v = √(25/m)
Answer:
F = 878.9 N
Explanation:
The electrostatic force of attraction or repulsion is given by Coulomb's Law as follows:
F = kq₁q₂/r²
where,
F = Force pf repulsion between balloons = ?
k = Coulomb's Constant = 9 x 10⁹ N.m²/C²
q₁ = q₂ = magnitudes of 1st and 2nd charge = 0.0025 C
r = distance between balloons = 8 m
Therefore,
F = (9 x 10⁹ N.m²/C²)(0.0025 C)(0.0025 C)/(8 m)²
<u>F = 878.9 N</u>
Answer: They will have equal final angular velocity.
Explanation:
Since the discs starts from rest and rotates about a fixed axis, they are subject to a constant net torque. The work done by the torque during the second revolution is as the work done during the first revolution.
The four disc will turn through equal angles in equal times.
Answer:
7) λ = 0.5 m, 8) f = 4.8 10¹⁴ Hz
Explanation:
The speed of an electromagnetic wave is
c = λ f
where c is the speed of light in vacuum c = 3 10⁸ m / s
7) indicate the frequency f = 6.0 10⁸ Hz
we do not know the wavelength
λ = c / f
we calculate
λ = 3 10⁸ / 6.0 10⁸
λ = 0.5 m
8) indicate the wavelength λ = 6.25 10-7 m
we do not know the frequency
f = c / λ
we calculate
f = 3 10⁸ / 6.25 10⁻⁷
f = 0.48 10¹⁵ Hz
f = 4.8 10¹⁴ Hz