ray diagram for a double concave lens a focal length 4 cm when object placed at 3cm &5 cms in principle axis​

Give an example in which the electrical energy changes to light energy

An air-filled capacitor is formed from two long conducting cylindrical shells that are coaxial and have radii of 26 mm and 103 mm. the electric potential of the inner conductor with respect to the outer conductor is - 700 v (k = 1/4πε 0 = 8.99 × 109 n · m2/c2) the energy stored in a 1.0-m length of this capacitor is closest to

What are some important factors to consider when choosing a warm-up before your workout?