Answer:
R = 4.77 ohms
Explanation:
Four resistors are given such that,
R₁ = 2 ohms
R₂ = 3 ohms
R₃ = 5 ohms
R₄ = 10 ohms
Here, R₁ and R₂ in series. The equivalent is given by :
R₁₂ = R₁ + R₂
= 2 + 5
R₁₂ = 7 ohms
Similarly, R₃ and R₄ are in series. so,
R₃₄ = R₃ + R₄
= 10+5
R₃₄ = 15 ohms
Now, R₁₂ and R₃₄ are in parallel. So,
So, the equivalent resistance s 4.77 ohms.
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Answer:
0
7500J
7500J
Explanation:
Given parameters:
Mass of car = 600kg
Velocity = 5m/s
Unknown:
Original kinetic energy = ?
Final kinetic energy = ?
Work used = ?
Solution:
The kinetic energy of a body is the energy due to the motion of a body.
It can be solve mathematically using expression below;
K.E = 
m v²
where m is mass
v is velocity
original kinetic energy;
The car started at rest and v = 0, therefore K.E = 0
Final kinetic energy;
K.E = x 600 x 5² = 7500J
Work done:
Work done = Final K.E - Initial K.E = 7500 - 0 = 7500J
Answer:
E = 169.34 J
Explanation:
First, we need to find the frictional force between the back tire and the road. For that purpose, we use the following formula:
f = μR = μW
f = μmg
where,
f = frictional force = ?
μ = coefficient of friction between tire and road = 0.8
g = 9.8 m/s²
m = mass supported by back tire = (0.5)(90 kg) = 45 kg
Therefore,
f = (0.8)(45 kg)(9.8 m/s²)
f = 352.8 N
Now, for the heat energy we use the formula of work. Because, thermal energy will be equal to work done by frictional force:
E = W = fd
where,
E = Thermal Energy = ?
f = frictional force = 352.8 N
d = displacement = 48 cm = 0.48 m
Therefore,
E = (352.8 N)(0.48 m)
<u>E = 169.34 J</u>
Answer:
Time of flight=3.5 seconds
Speed at maximum height is 0
Explanation:
Φ=60°
initial velocity=u=20m/s
Acceleration due to gravity=g=9.8 m/s^2
Total time of flight=T
Final speed=v
question 1:
T=(2 x u x sinΦ)/g
T=(2 x 20 x sin60)/9.8
T=(2 x 20 x 0.8660)/9.8
T=34.64/9.8
T=3.5 seconds
Question 2
Speed at maximum height is 0
