Answer:
c)
Explanation:
A collision is said to be elastic when the total kinetic energy is the same after the collision. The speed of objects that are stuck together will always be less than the initial speed of the object that was in motion given that the other particle was at rest. It is because the kinetic energy of the system was due to the moving object. The objects have a greater overall mass when they are stuck. If the kinetic energy is the same and the mass increases, the velocity must decrease.
Magnification is the ratio of the image's height to object's height or the ratio of image distance to object distance.
That is; Magnification = height of the image/height of object= image distance/object distance
= x/4 = 21/8
x = (21 × 4)/8
= 10.5 cm
The height of the image is 10.5 cm
The mirror in this case is a concave mirror, since when the object is placed between the principal focus and the concave mirror, it forms a virtual magnified image on the other side ofthe mirror (that is why we have a negative image distance).
Explanation:
Since the current flowing through an ideal capacitor is described by equation:
![i_{C}=C\frac{dV}{dt}](https://tex.z-dn.net/?f=i_%7BC%7D%3DC%5Cfrac%7BdV%7D%7Bdt%7D)
for voltage across the capacitor constant with time the current is:
![i_{C}=\frac{d(Constant)}{dt}=0](https://tex.z-dn.net/?f=i_%7BC%7D%3D%5Cfrac%7Bd%28Constant%29%7D%7Bdt%7D%3D0)
Open switch has this characteristics (Constant voltage and zero current).
I think it will go down like decrease minus or whatever you call it