Choose the correct (a) Which of the following formula is used to determine the force?
(i) f=m/a
(ii) f= a/m
(iii) f= ma
(iv) f = ma
(b) Frictional force is due to the
(1) Falling of a body
(ii) Smooth surfaces between two bodies
(iii) moving in a circular path
(iv) rough surfaces between two bodies
(c) A body moving in a circular path experiences a force towards the center is
(i) frictional force
(ii) centripetal force
(iii) gravitational force
(iv) magnetic force
(d) The attraction or repulsion between two charged bodies is due to
(i) gravity
magnetic force
(111) electrostatic force
(iv) centripetal force
(e) A magnet attracts iron, cobalt and nickel due to
(1) electrostatc force
(ii) magnetic force
(iii) gravitational force
(iv) centripetal force
(f) The S. I. unit of acceleration is
(i) m/s2
(ii) m/s
(ii) m
(iv) N
(g) Speed is a
(i) scalar quantity
(ii) vector quantity
(iii) both
(iv) none

If 10.g of agno3 is available, what volume of 0.25 m agno3 can be prepared

A3.37-mg sample of protein was chemically digested to convert its nitrogen into ammonia and then diluted to 100.0 ml. then 10.0 ml of this solution was placed in a 50-ml volumetric flask and treated with 5 ml of phenol solution plus 2 ml of sodium hypochlorite solution. the sample was diluted to 50.0 ml, and the absorbance at 625 nm was measured in a 1.00-cm cuvette and found to be 0.486. for reference, a standard solution was prepared from 10.0 mg of nh4cl (molar mass = 53.49 grams/mole) dissolved in 1.00 l of water. then 10.0 ml of this standard was placed in a 50-ml volumetric flask, treated in the same manner as the unknown, and the absorbance found to be 0.323. finally, a reagent blank was prepared using distilled water in place of unknown, it was treated in the same manner as the unknown, and the absorbance found to be 0.076. calculate the weight percent of nitrogen in the protein.

Apiece of copper has a temperature of 75.6 0c. when the metal is placed in 100.0 grams of water at 19.1 0c, the temperature rises by 5.5 0c. what is the mass of the metal?