้ๅ้ใจๅ็ฉใฎ้ขไฟใ็ขบ่ชใใๅบๆฌๅ้กใงใใใๅ ร ๆ้ = ้ๅ้ใฎๅคๅใใจใใ้ขไฟใ็่งฃใใฆใใใใๅใใใพใใ
ๅ็ฉใฏใๅใๆ้ใซใใใฃใฆไธใใๅนๆใฎ็ท้ใใ้ๅ้ใฏใๅใใฆใใ็ฉไฝใฎๅขใใใไธก่ ใฎ้ขไฟใฏ ๅ็ฉ = ้ๅ้ใฎๅคๅใใใใฏ้ๅๆน็จๅผ \(F = ma\) ใฎไธก่พบใซ \(\Delta t\) ใใใใฆ็ฉๅใใๅฝขใจ็ญไพกใงใใ
้ๅ้ใจๅ็ฉใฎ้ขไฟใๆญฃใใ่ฟฐในใ้ธๆ่ขใ้ธใถใๅบๆฌ็ใชๅฎ็พฉใจๅ ฌๅผใ็ขบ่ชใใๅ้กใ
ๅ็ฉใจ้ๅ้ใฏๅใๅไฝ๏ผNยทs = kgยทm/s๏ผใใๅ็ฉ = ้ๅ้ใฎๅคๅใใจใใ้ขไฟใ็ฅใฃใฆใใใฐใ้ๅ้ใฎๅคๅใๆฑใใใฎใซ็ดๆฅ Fยทฮt ใ่จ็ฎใใใฐใใใ้ๅใจใใซใฎใผใฎๅคๅ๏ผ\(\dfrac{1}{2}mv^2\) ใฎๅคๅ๏ผใจๆททๅใใชใใใจใ