The correct answer is B. wrap more coils of wire around the nail. This is how you can increase its magnetic strength. Thank you for posting your question. I hope this answer helped you. Let me know if you need more help.
Answer:
b) 0.5 m/s
Explanation:
let V be the averare speed of the object.
the average speed is given by:
V = total distance / total time
= (20+20)/(30+50)
= 0.5 m/s
Therefore, the average speed of the object is 0.5 m/s.
<span>The speed is a scalar quantity which by definition is the distance traveled per unit of time. Unit for speed is: km/h. (how many km the object is moved for one hour) or mph (miles per hour).
From the given option D. A dog runs an average 8 mph. (this means that a dog is moving 8 miles per hour).
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Answer:
0.3 m
Explanation:
Initially, the package has both gravitational potential energy and kinetic energy. The spring has elastic energy. After the package is brought to rest, all the energy is stored in the spring.
Initial energy = final energy
mgh + ½ mv² + ½ kx₁² = ½ kx₂²
Given:
m = 50 kg
g = 9.8 m/s²
h = 8 sin 20º m
v = 2 m/s
k = 30000 N/m
x₁ = 0.05 m
(50)(9.8)(8 sin 20) + ½ (50)(2)² + ½ (30000)(0.05)² = ½ (30000)x₂²
x₂ ≈ 0.314 m
So the spring is compressed 0.314 m from it's natural length. However, we're asked to find the additional deformation from the original 50mm.
x₂ − x₁
0.314 m − 0.05 m
0.264 m
Rounding to 1 sig-fig, the spring is compressed an additional 0.3 meters.
