Answer:
Matter is anything that has mass
Explanation:
The word "matter" refers to anything that has mass, either organic or inorganic. Matter is made up of atoms, which consists of a nucleus (made up of protons, positively charged, and neutrons, electrically neutron) and electrons which revolve around the nucleus.
The number of protons in the atom determine the element: there are more than 100 different elements in nature, with different properties depending on the number of electrons they have.
Matter can be in three different states also:
- solid: the atoms are tightly bond to each other, so they cannot move
- liquids: atoms are not bond to each other, so they can slide past each other, but still they have some intermolecular forces that keep them close to each other
- gas: atoms are free to move, as there are no forces that keep them close to each other
Answer:
Explanation:
Calories to be burnt = 3500 - 2500 = 1000 Cals .
Efficiency of conversion to mechanical work is 25 % .
Work needed to burn this much of Cals = 1000 x 100 / 25 = 4000 Cals.
4000 Cals = 4.2 x 4000 = 16800 J .
Work done in one jump = kinetic energy while jumping
= 1/2 m v²
= .5 x 70 x 3.3²
= 381.15 J .
Number of jumps required = 16800 / 381.15
= 44 .
Answer:
187 J
Explanation:
First Law of Thermodynamics :
ΔQ = ΔW + ΔU
ΔQ : Heat. If it added to system then positive and if it is rejected by system then negative.
ΔW : Work. If it done by the system then positive and if it is done on system then negative.
ΔU : Internal Energy. If it positive then temperature of system increased and if it is negative then temperature of system decreased.
ΔQ = 79 J
ΔW = - 108 J
ΔU = ?
substituting the value in the equation:
79 = -108 + ΔU
∴ ΔU = 187 J
