A projectile has x=3t and y=4t−5t², with x,y in metres and t in seconds. Find its initial speed (m/s).
Physics · Mixed Chapter
JEE Main Practice

Question

A projectile has x=3t and y=4t−5t², with x,y in metres and t in seconds. Find its initial speed (m/s).

G1 Physics · Accepted Answer

Step 1: Velocity components are time derivatives: vₓ=dx/dt=3 and vᵧ=dy/dt=4−10t. Step 2: At launch t=0, uₓ=3 m/s and uᵧ=4 m/s. Step 3: u=√(3²+4²)=5 m/s.