Energy

Consider the following event in the photochemical conversion of light energy into chemical conversion of light energy by chlorophyll during photosynthesis I) Energy transformation (light energy rarr ATP ) II) Absorption of quantum of energy III)Ejection of electron from P_(680) IV) Transfer of light energy (resource transfer )

Study the following graph of the concept of activation energy given below. Select the correct option for stages labeled A to D (a) {:(A,B,C,D),("Transition state","Potential energy", "Activation energy without enzyme","Activation energy with enzyme"):} (b) {:(A,B,C,D),("kinetic energy","Potential energy", "Activation energy without enzyme","Activation energy with enzyme"):} (c) {:(A,B,C,D),("kinetic energy","Transition energy", "Activation energy without enzyme","Activation energy with enzyme"):} (d) {:(A,B,C,D),("Potential energy","Transition energy", "Activation energy without enzyme","Activation energy with enzyme"):}

Define mechanical energy and law of conservation of mechanical energy. Prove conversion of gravitational potential energy in to kinetic energy by the help of law of conservation of mechanical energy. Also draw graph between energy and height.

Which of the following statemente is / are INCORRECT? (a) Mechanical energy is the sum of kinetic energy and potential energy. (b) Potential energy is a relative quantity. It depends on the choice of reference point. (c ) Kinetic energy must be non negative. (d) Potential energy must be postive.

Bond energies are equal to dissociation energies in case of :

As an electron makes a transition from an excited state to the ground state of a hydrogen like atom/ion (a) kinetic energy, potential energy and total energy decrease (b) kinetic energy decreases, potential energy increases but total energy remains same (c ) kinetic energy and total energy decrease but potential energy increases (d) its kinetic energy increases but potential energy and total energy decrease