What is the effective resistance (in Ω) of two resistors 21 Ω and 28 Ω connected in parallel?

 

What does the symbol R in electricity stand for ?

An echo is returned in 3 s. What is the distance of the reflecting surface from the source, considering the speed of sound as 342 ms-1?

A 5 kg object is raised through a height of 4 m. The work done by the force of gravity acting on the object is (take g = 10 m/s2)

Any body kept in a fluid experiences an upward force called _____________.

Find the resistance (in mega Ω) of a wire of length 10 m, cross sectional area 1 cm2 and made of a material of resistivity 100 Ωm.

A charge of 2 C passes from one point to the other in a circuit. If the potential difference between the two points is 5 V, the amount of work done is

An object is placed at the centre of curvature of a concave mirror. Its image is formed at

The energy released at the end of digestion is in the form of