Answer:
4. Both points have the same instantaneous angular velocity
Explanation:
Angular velocity is a measure of the the number of rotations per unit time. This does not depend on the radius of the wheel. Hence, all points on the wheel have the same angular velocity. This invalidates option 1.
The centripetal acceleration is given by the product to the square of the angular velocity and the radius or distance from the centre. A and B are located at different distances from the centre. Hence, they have different centripetal acceleration. This invalidates option 2.
The tangential acceleration depends on the linear velocity which itself is a product of the angular velocity and the distance from the centre. Hence, it is different for both points because they are at different distances from the centre.
Since both A and B are fixed points on the wheel, they move through equal angles in the same time. In fact, for any other fixed point, they all move through the same angle in the same time. This invalidates option 5.
Answer:
Part of that kinetic energy created by moving of particles in object is transformed to heat that can be measured by thermometer.
Explanation:
By moving object creates kinematic energy, that is true. In object itself small particles are moving and creating kinetic energy as well. Part of that kinetic energy created by moving of particles in object is transformed to heat that can be measured by thermometer.
Same thing is that when you run or exercise your body temperature is raising(because of moving ).
When you sit your body does not raise temperature.
<span>Balloons are blown up, and then rubbed against your shirt many times. The balloon then touches the ceiling. When released, the balloon remains stuck to the ceiling. The balloon is charged by contact. The ceiling has a neutral charge. The charged balloon induces a slight surface charge on the ceiling opposite to the charge on the balloon. Balloon and ceiling electric charges are opposite in sign, so they will attract each other. Since both the balloon and the ceiling are insulators, charge can not flow from one to the other. The charge on the balloon is fixed on the balloon and the charge on the ceiling remains fixed to the ceiling. It just so happens that the<span> electrostatic force the ceiling exerts on the balloon is sufficient to hold the balloon in place (i.e. overcomes gravity, etc.).</span></span>
Answer:
0.025 A
Explanation:
A = 50 cm^2 = 50 x 10^-4 m^2
B2 = 6 T, B1 = 2 T
db = 6 - 2 = 4 T
dt = 2 s
R = 0.4 ohm
Let i be the magnitude of induced current and e be the induced emf.
According to the Faraday's law of electromagnetic induction
e = dФ / dt
e = A dB / dt
e = 50 x 10^-4 x 4 / 2 = 0.01 V
i = e / R = 0.01 / 0.4 = 0.025 A
