Derive three equations of motion graphically.
(please answer)
Answers
Answer:
first equation of motion u =v+at
second equation of motion s =ut+1/2 at2
third equation of motion v2 =u2+2as.
here is impossible to draw the graphic method.
ғɪʀsᴛ
ɪɴ ᴛʜᴇ ᴀʙᴏᴠᴇ ɢʀᴀᴘʜ,
ᴛʜᴇ ᴠᴇʟᴏᴄɪᴛʏ ᴏғ ᴛʜᴇ ʙᴏᴅʏ ᴄʜᴀɴɢᴇs ғʀᴏᴍ ᴀ ᴛᴏ ʙ ɪɴ ᴛɪᴍᴇ ᴛ ᴀᴛ ᴀ ᴜɴɪғᴏʀᴍ ʀᴀᴛᴇ.
ʙᴄ ɪs ᴛʜᴇ ғɪɴᴀʟ ᴠᴇʟᴏᴄɪᴛʏ ᴀɴᴅ ᴏᴄ ɪs ᴛʜᴇ ᴛᴏᴛᴀʟ ᴛɪᴍᴇ ᴛ.
ᴀ ᴘᴇʀᴘᴇɴᴅɪᴄᴜʟᴀʀ ɪs ᴅʀᴀᴡɴ ғʀᴏᴍ ʙ ᴛᴏ ᴏᴄ, ᴀ ᴘᴀʀᴀʟʟᴇʟ ʟɪɴᴇ ɪs ᴅʀᴀᴡɴ ғʀᴏᴍ ᴀ ᴛᴏ ᴅ, ᴀɴᴅ ᴀɴᴏᴛʜᴇʀ ᴘᴇʀᴘᴇɴᴅɪᴄᴜʟᴀʀ ɪs ᴅʀᴀᴡɴ ғʀᴏᴍ ʙ ᴛᴏ ᴏᴇ (ʀᴇᴘʀᴇsᴇɴᴛᴇᴅ ʙʏ ᴅᴏᴛᴛᴇᴅ ʟɪɴᴇs).
ғᴏʟʟᴏᴡɪɴɢ ᴅᴇᴛᴀɪʟs ᴀʀᴇ ᴏʙᴛᴀɪɴᴇᴅ ғʀᴏᴍ ᴛʜᴇ ɢʀᴀᴘʜ ᴀʙᴏᴠᴇ:
ᴛʜᴇ ɪɴɪᴛɪᴀʟ ᴠᴇʟᴏᴄɪᴛʏ ᴏғ ᴛʜᴇ ʙᴏᴅʏ, ᴜ = ᴏᴀ
ᴛʜᴇ ғɪɴᴀʟ ᴠᴇʟᴏᴄɪᴛʏ ᴏғ ᴛʜᴇ ʙᴏᴅʏ, ᴠ = ʙᴄ
ғʀᴏᴍ ᴛʜᴇ ɢʀᴀᴘʜ, ᴡᴇ ᴋɴᴏᴡ ᴛʜᴀᴛ
ʙᴄ = ʙᴅ + ᴅᴄ
ᴛʜᴇʀᴇғᴏʀᴇ, ᴠ = ʙᴅ + ᴅᴄ
ᴠ = ʙᴅ + ᴏᴀ (sɪɴᴄᴇ ᴅᴄ = ᴏᴀ)
ғɪɴᴀʟʟʏ,
ᴠ = ʙᴅ + ᴜ (sɪɴᴄᴇ ᴏᴀ = ᴜ) (ᴇǫᴜᴀᴛɪᴏɴ )
ɴᴏᴡ, sɪɴᴄᴇ ᴛʜᴇ sʟᴏᴘᴇ ᴏғ ᴀ ᴠᴇʟᴏᴄɪᴛʏ-ᴛɪᴍᴇ ɢʀᴀᴘʜ ɪs ᴇǫᴜᴀʟ ᴛᴏ ᴀᴄᴄᴇʟᴇʀᴀᴛɪᴏɴ ᴀ,
sᴏ,
ᴀ = sʟᴏᴘᴇ ᴏғ ʟɪɴᴇ ᴀʙ
ᴀ = ʙᴅ/ᴀᴅ
sɪɴᴄᴇ ᴀᴅ = ᴀᴄ = ᴛ, ᴛʜᴇ ᴀʙᴏᴠᴇ ᴇǫᴜᴀᴛɪᴏɴ ʙᴇᴄᴏᴍᴇs:
ʙᴅ = ᴀᴛ (ᴇǫᴜᴀᴛɪᴏɴ )
ɴᴏᴡ, ᴄᴏᴍʙɪɴɪɴɢ ᴇǫᴜᴀᴛɪᴏɴ & , ᴛʜᴇ ғᴏʟʟᴏᴡɪɴɢ ɪs ᴏʙᴛᴀɪɴᴇᴅ:
ᴠ = ᴜ + ᴀᴛ
sᴇᴄᴏɴᴅ
From the graph above, we can say that
Distance travelled (s) = Area of figure OABC = Area of rectangle OADC + Area of triangle ABD
s=(12AB×BD)+(OA×OC)
Since BD = EA, the above equation becomes
s=(12AB×EA)+(u×t)
As EA = at, the equation becomes
s=12×at×t+ut
On further simplification, the equation becomes
s=ut+12at2
ᴛʜɪʀᴅ
ғʀᴏᴍ ᴛʜᴇ ɢʀᴀᴘʜ, ᴡᴇ ᴄᴀɴ sᴀʏ ᴛʜᴀᴛ
ᴛʜᴇ ᴛᴏᴛᴀʟ ᴅɪsᴛᴀɴᴄᴇ ᴛʀᴀᴠᴇʟʟᴇᴅ, s ɪs ɢɪᴠᴇɴ ʙʏ ᴛʜᴇ ᴀʀᴇᴀ ᴏғ ᴛʀᴀᴘᴇᴢɪᴜᴍ ᴏᴀʙᴄ.
ʜᴇɴᴄᴇ,
s = ½ (sᴜᴍ ᴏғ ᴘᴀʀᴀʟʟᴇʟ sɪᴅᴇs) × ʜᴇɪɢʜᴛ
s=(ᴏᴀ+ᴄʙ)×ᴏᴄ
sɪɴᴄᴇ, ᴏᴀ = ᴜ, ᴄʙ = ᴠ, ᴀɴᴅ ᴏᴄ = ᴛ
ᴛʜᴇ ᴀʙᴏᴠᴇ ᴇǫᴜᴀᴛɪᴏɴ ʙᴇᴄᴏᴍᴇs
s= ½ (ᴜ+ᴠ) × ᴛ
ɴᴏᴡ, sɪɴᴄᴇ ᴛ = (ᴠ – ᴜ)/ ᴀ
ᴛʜᴇ ᴀʙᴏᴠᴇ ᴇǫᴜᴀᴛɪᴏɴ ᴄᴀɴ ʙᴇ ᴡʀɪᴛᴛᴇɴ ᴀs:
s= ½ ((ᴜ+ᴠ) × (ᴠ-ᴜ))/ᴀ
ʀᴇᴀʀʀᴀɴɢɪɴɢ ᴛʜᴇ ᴇǫᴜᴀᴛɪᴏɴ, ᴡᴇ ɢᴇᴛ
s= ½ (ᴠ+ᴜ) × (ᴠ-ᴜ)/ᴀ
s = (ᴠ-ᴜ)/ᴀ
ᴛʜɪʀᴅ ᴇǫᴜᴀᴛɪᴏɴ ᴏғ ᴍᴏᴛɪᴏɴ ɪs ᴏʙᴛᴀɪɴᴇᴅ ʙʏ sᴏʟᴠɪɴɢ ᴛʜᴇ ᴀʙᴏᴠᴇ ᴇǫᴜᴀᴛɪᴏɴ:
ᴠ = ᴜ+ᴀs