A charged particle is placed in a uniform magnetic field and negligible gravitational field. When released it will exhibit constant

Constant velocity

Explanation:

The Lorentz force acting on the particle is given by F = Bqvsinθ where B =    magnetic field strength, q = charge, v = speed of charge and θ = angle between v and B.

If the charge is released with a velocity, v, it experiences a force, F = Bqvsinθ. Since F = ma, Bqvsinθ = ma and a = Bqvsinθ/m. So, since all the variables are constant, the charged particle exhibits no acceleration since the velocity is constant.

when jerome paddle in flowing river towards east the net speed of jerome will increase

so the net speed of jerome will be given as

now the speed of paul will be same as it is given as he is running on the ground

so

so here we can say since the speed of jerome is more so he will win the race

now as we know the distance so the time difference is given as

so jerome will reach first and the time difference will be 203.55 s or 3.4 min

you'd use the equation that establishes a relationship between  energy  and  wavelength, which looks like this

e=h⋅cλ, where

λ  - the wavelength of the photon; c  - the speed of light, usually given as  3⋅108m/s; h  -  planck's constant, equal to  6.626⋅10−34j s

plug the value you were given for the energy of the photon in the above equation to get the wavelength

e=h⋅cλ⇒λ=h⋅ce

λ=6.626⋅10−34js⋅3⋅108ms−1.257⋅10−24j=1.581⋅10−1m