No. Mechanical energy is not conserved. There's quite a bit of friction on the slide. So some of the potential energy is lost to heat on the way down, and the child arrives at the bottom with hot pants and less kinetic energy than you might expect.
Answer: The weight of a girl with a mass of 40kg is 392.266 Newtons.
Explanation:
Answer: Gamma rays, x-rays, ultraviolet rays, visible light, and infrared rays.
Explanation:
formula: <u>Mass</u>
Density x volume
2a) m=10kg v=0.3m³
10÷0.3=33.3 kg/m
2b) m = 160 kg V=0.1m³
160÷0.1=1600 kg/m
2c) m = 220 kg V = 0.02m³
220÷0.02=11000 kg/m
A wooden post has a volume of 0.025m³ and a mass of 20kg. Calculate its density in kg/m.
density = volume ÷ mass
20÷ 0.025=800 kg/m
Challenge: A rectangular concrete slab is 0.80m long, 0.60 m wide and 0.04m thick. Calculate its volume in m³.
Formula : Length x width x height = Volume
0.80 x 0.60 x 0.04 = 0.0192m³
B) The mass of the concrete slab is 180 kg. Calculate its density in kg/m.
density = volume ÷ mass
180 ÷ 0.0192 = 9375 kg/m
Explanation:
a. Net force is mass times acceleration (Newton's second law).
∑F = ma
∑F = (5.0 kg) (2.0 m/s²)
∑F = 10 N
b. The net force is the sum of the individual forces.
10 N = F − 5 N
F = 15 N
c. Friction force here is mgμ.
mgμ = 5 N
(5.0 kg) (10 m/s) μ = 5 N
μ = 0.1
