A 50 - kg box rests on horizontal floor for which coefficient of frict...
Initially checking whether towing force can overcome the static friction force or not.
Friction force (f) = μN = μmg = 0.3 × 50 × 10 = 150 N
∴ Net force on box = 400 – 150 = 250 N
⇒ 250 = ma
Velocity after 5 second
V = u + at = 0 + 5 × 5 = 25 m/s
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A 50 - kg box rests on horizontal floor for which coefficient of frict...
Given data:
Mass of the box, m = 50 kg
Coefficient of friction, μ = 0.3
Towing force, F = 400 N
Acceleration due to gravity, g = 10 m/s^2
Time, t = 5 s
To find:
Velocity of the box after 5 seconds from rest
Firstly, we need to calculate the frictional force acting on the box. The frictional force can be found using the equation:
Frictional force, F_friction = μ × Normal force
The normal force acting on the box is equal to the weight of the box, which can be calculated as:
Normal force, N = mg
Where,
m = mass of the box
g = acceleration due to gravity
Substituting the values, we get:
Normal force, N = 50 kg × 10 m/s^2 = 500 N
Now, we can calculate the frictional force:
F_friction = 0.3 × 500 N = 150 N
The net force acting on the box can be found by subtracting the frictional force from the applied force:
Net force, F_net = F - F_friction
Substituting the values, we get:
F_net = 400 N - 150 N = 250 N
Next, we can calculate the acceleration of the box using Newton's second law of motion:
F_net = ma
Substituting the values, we get:
250 N = 50 kg × a
Simplifying, we get:
a = 250 N / 50 kg = 5 m/s^2
Finally, we can calculate the velocity of the box after 5 seconds using the equation of motion:
v = u + at
Where,
v = final velocity
u = initial velocity (0 m/s)
a = acceleration
t = time
Substituting the values, we get:
v = 0 + 5 m/s^2 × 5 s = 25 m/s
Therefore, the velocity of the box after 5 seconds from rest is 25 m/s, which corresponds to option D.
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