Answer:
The rotational kinetic energy of the hoop and the instantaneous change rate of the kinetic energy are 2.25 J and 15 J.
Explanation:
Given that,
Mass = 2 kg
Radius = 0.5 m
Angular speed = 3 rad/s
Force = 10 N
(I). We need to calculate the rotational kinetic energy
Using formula of kinetic energy
(II). We need to calculate the instantaneous change rate of the kinetic energy
Using formula of kinetic energy
On differentiating
....(I)
Using newton's second law
Put the value of a in equation (I)
Hence, The rotational kinetic energy of the hoop and the instantaneous change rate of the kinetic energy are 2.25 J and 15 J.
Answer:
Explanation:
We have given given the final angular velocity
And
Displacement
We have to find the angular acceleration
According to law of motion
So
In question we have tell about magnitude only so
Density = (mass) / (volume) <=== <u>Memorize this</u> !
Mass = 6 g
Volume = 12 mL
Density = (6 g) / (12 mL)
Density = (6/12) (g/mL)
1 mL is the same volume as 1 cm³
<em>Density = 0.5 g/cm³</em>
Answer:
Explanation:
The charges will repel each other and go away with increasing velocity , their kinetic energy coming from their potential energy .
Their potential energy at distance d
= kq₁q₂ / d
= 9 x 10⁹ x 36 x 10⁻¹² / 2 x 10⁻² J
= 16.2 J
Their total kinetic energy will be equal to this potential energy.
2 x 1/2 x mv² = 16.2
= 3 x 10⁻⁶ v² = 16.2
v = 5.4 x 10⁶
v = 2.32 x 10³ m/s
When masses are different , total P.E, will be divided between them as follows
K E of 3 μ = (16.2 / 30+3) x 30
= 14.73 J
1/2 X 3 X 10⁻⁶ v₁² = 14.73
v₁ = 3.13 x 10³
K E of 30 μ = (16.2 / 30+3) x 3
= 1.47 J
1/2 x 30 x 10⁻⁶ x v₂² = 1.47
v₂ = .313 x 10³ m/s