Answer:
the answer is B
Explanation:
The atomic mass of an atom is the sum of the protons plus neutrons it has.
Answer:
N = 6.67 N
Explanation:
The frictional or frictional force is a force that arises from the contact of two bodies and opposes movement.
The friction is due to imperfections and roughness, mainly microscopic, that exist on the surfaces of the bodies. Upon contact, these roughnesses engage with each other making movement difficult. To minimize the effect of friction, either the surfaces are polished or lubricated, since the oil fills the imperfections, preventing them from snagging.
As the frictional force depends on the materials and the force exerted on one another, its magnitude is obtained by the following expression:
f = μ*N Formula (1)
where:
f is the friction force (N)
μ is the coefficient of friction
N is the normal force (N)
Data
f = 0.2 N : frictional force between the steel spatula and the Oiled Steel frying pan
μ = 0.03 :coefficient of kinetic friction between the two materials
Calculating of normal force
We replace data in the formula (1)
f = μ*N
0.2 = 0.03*N
N = 0.2 / 0.03
N = 6.67 N
Answer:
1. 20.54m/s
2. 1.52s
Explanation:
QUESTION 1:
The speed the stone impact the ground is the final speed/velocity, which can be calculated using the formula:
v² = u² + 2as
Where;
v = final velocity (m/s)
u = initial velocity (m/s)
a = acceleration due to gravity (m/s²)
s = distance (m)
From the provided information, u = 5.65m/s, v = ?, s = 19.9m, a = 9.8m/s²
v² = 5.65² + 2 (9.8 × 19.9)
v² = 31.9225 + 2 (195.02)
v² = 31.9225 + 390.04
v² = 421.9625
v = √421.9625
v = 20.5417
v = 20.54m/s
QUESTION 2:
Using v = u + at
Where v = final velocity (m/s) = 20.54m/s
t = time (s)
u = initial velocity (m/s) = 5.65m/s
a = acceleration due to gravity (m/s²)
v = u + at
20.54 = 5.65 + 9.8t
20.54 - 5.65 = 9.8t
14.89 = 9.8t
t = 14.89/9.8
t = 1.519
t = 1.52s
KE = (1/2)·(mass)·(speed)²
KE = (1/2)·(50 kg)·(18 m/s)²
KE = (25 kg)·(324 m²/s²)
KE = 8,100 kg-m²/s²
KE = 8,100 Joules