Answer:
c. Both Technicians A and B
Explanation:
Disc brakes are self-adjusting because the pistons in the brakes are much larger in diameter than the ones in the master cylinder. If the brake pistons retracted into their cylinders, it might take several applications of the brake pedal to pump enough fluid into the brake cylinder to engage the brake pads. The height of the brake pedal is also necessary because if they become lower the disc brake pads will wear, this is why self-adjustment is important and disc brake pads usually have a piece of metal on them called a wear indicator to warn of wearing. Also when disc break pads wear, the fluid level in the master cylinder drops, armed with this knowledge of low master cylinder fluid level one can inspect the disc pads for wear. Thus both Technicians A and B are correct.
Answer: the same direction I.e to the left.
Explanation:
The component perpendicular to the contact surface is such that will stop the relative motion and, in case of elastic collision like here, return the system to the same kinetic energy. So ball hitting immovable surface will have the same speed (magnitude of velocity) as before the collision.
There will also be parallel force caused by friction, but it has to be treated separately for two reasons:
The perpendicular force is limited to coefficient of friction times the normal force. If that is not enough to stop the ball, it will skid on the surface.The perpendicular force, and this depends on the specific geometry, does not pass through the centre of mass of the ball. Therefore it imparts a moment on the ball that causes it to start rotating. And once the ball is rotating so that the point of contact is stationary, there is no momentum to cause any friction force anymore and the friction force disappears and stops decelerating the ball.
So what happens is that the vertical component of the velocity will be reversed, while the horizontal component will be somewhat reduced with the corresponding amount of kinetic energy transferred to energy of rotation. The rotation will always eliminate the friction force before the horizontal component of velocity is zeroed, so the ball will always continue in the same direction, just a bit slower.
If you instead threw an elastic box (which could not start rotating freely) it could actually bounce back.
Answer:
720 J
Explanation:
Kinetic Energy = 1/2 * m *(v*v)
M= 90 kg
V=4 m/s
KE=1/2 * 90 * (4*4)
KE= 45*16= 720 J
Electrical to light & electrical to sound (in commentry) & sometimes battery loudspeakers are used so chemical to sound
An alpha particle is identical to a helium nucleus. The correct option
among all the options given in the question is option "A". In case of
both the alpha particle nucleus and helium nucleus, there are two protons and two neutrons. Alpha particles are generally formed during the process of alpha decay. They can also be produced in other ways.
