A body of mass 20 kh changes its velocity from 5m/s to 17 m/s in 3 seconds. find the force applied on this body

80 N.

Explanation:

The following data were obtained from the question:

Mass (m) = 20 Kg

Initial velocity (u) = 5 m/s

Final velocity (v) = 17 m/s

Time (t) = 3 secs

Force (F) =.?

Next, we shall determine the acceleration of the body.

Acceleration is simply defined as the rate of change of velocity with time. Mathematically, it is expressed as:

Acceleration = change of velocity /time

Acceleration (a) = (final velocity (v) – initial velocity (u)) / time (t)

a = (v – u) /t

With the above formula, we can obtain the acceleration of the body as follow:

Initial velocity (u) = 5 m/s

Final velocity (v) = 17 m/s

Time (t) = 3 secs

Acceleration (a) =?

a = (v – u) /t

a = (17 – 5) /3

a = 12/3

a = 4 m/s²

Finally, we shall determine the force applied to the body as follow:

Force (F) = mass (m) x acceleration (a)

F = ma

Mass (m) = 20 Kg

Acceleration (a) = 4 m/s²

Force (F) =.?

F = ma

F = 20 x 4

F = 80 M.

Therefore, the force applied on the body is 80 N.

e) none of the above answers are correct

  1.the balanced   chemical equation is as below

cu +   2 ag(no)₃ → cu(no₃)₂   +2 ag

2.the   much silver   produced   is   50.9 g

step 1: find the   moles of cu

moles =   mass÷   molar mass

  from periodic table the molar mass of cu = 63.5 g/mol

moles is therefore = 15.00 g÷ 63.5 g/mol = 0.236   moles

step 2: use the mole ratio to determine the   moles of ag

from equation above   cu: ag   is 1: 2

therefore the moles of ag   =0.236   moles   x 2/1 =0.472   moles

step 3: find the mass   of ag

mass = moles x molar mass

from periodic table   the molar mass of ag =107.87 g/mol

mass   = 0.472   moles x 107.87 g/mol = 50.9 g

3.   the   much   silver   collected worth is   1.797 oz

  convert   50.9 g   to oz

that is   1 gram = 0.0353 oz

          50.9 grams =?   oz

by cross multiplication

={(50.9 grams x 0.0353 oz) / 1   gram}   =1.797 oz