Question

9. A hockey puck has a mass of 0.20 kg. If the hockey puck
is moving with 75 J of kinetic energy, what is its speed? Show all your work.

Answer 1

Given:-

• Mass, m = 0.20 kg

• Kinetic Energy ,KE = 75 J

To Find:-

• Speed ,V

Solution:-

As we know that Kinetic Energy is the energy possess by body due to its motion.

• KE = 1/2mv²

Where,

KE is the Kinetic Energy

m is the mass

v is the speed/velocity

Substitute the value we get

→ 75 = 1/2×0.20 × v²

→ 75 = 0.10 × v²

→ 75/0.10 = v²

→ v² = 750/1

→ v² = 750

→ v = √750

→ v = 27.38 m/s

Therefore, the speed of hockey puck is 27.38 m/s.

Answer 2

♣ɢɪᴠᴇɴ:–

• Mass (m) = 0.20 kg

• Kinetic energy (k.e) = 75 J

♣ᴛᴏ ғɪɴᴅ:–

• The speed (s) = ?

♣sᴏʟᴜᴛɪᴏɴ:–

We can very easily calculate the speed by using this formula:—

• k.e = 1/2ms²

→ 75 = 1/2 × 0.20 × s²

→ 75 = 0.10 × s²

→ 75/0.10 = s²

→ 7500/10 = s²

→ 750 = s²

→ s = √750

→ s = 27.38 m/s

♣ᴀɴsᴡᴇʀ:–

• The speed of the hockey puck = 27.38 m/s