Answer:
1. Battery
2. Copper wire
3. Nail or piece of metal (zinc, iron, or steel).
Answer:
(C) greater than zero but less than 45° above the horizontal
Explanation:
The range of a projectile is given by R = v²sin2θ/g.
For maximum range, sin2θ = 1 ⇒ 2θ = sin⁻¹(1) = 90°
2θ = 90°
θ = 90°/2 = 45°
So the maximum horizontal distance R is in the range 0 < θ < 45°, if θ is the angle above the horizontal.
Speed has the dimensions of distance divided by time. The SI unit of speed is themetre<span> per second, but the most common unit of speed in everyday usage is the kilometre per </span>hour<span> or, in the US and the UK, miles per </span>hour<span>. For air and marine travel the knot is commonly used.</span>