Question

How long will it take a force of 10N
Stop a mass of
2.5kg
which is at 20m/s
​

Answer 1

ᴍᴀss ᴏғ ᴛʜᴇ ʙᴏᴅʏ = 2.5 ᴋɢ

ɪɴɪᴛɪᴀʟ ᴠᴇʟᴏᴄɪᴛʏ ᴜ = 20 ᴍ/s

ғɪɴᴀʟ ᴠᴇʟᴏᴄɪᴛʏ ᴠ = 0 ᴍ/s

ғᴏʀᴄᴇ ғ = 10 ɴ sɪɴᴄᴇ ᴠ < ᴜ, sᴏ

ᴀᴄᴄᴇʟᴇʀᴀᴛɪᴏɴ ᴡɪʟʟ ʜᴀᴠᴇ ᴀ ɴᴇɢᴀᴛɪᴠᴇ sɪɢʜ ᴀ = -4 ᴍ/s2

ᴛ = ᴠ-ᴜ/ᴀ = 0-20/-4 = 5s