If P is the force acting on the body, m is the mass of the body and a is the acceleration of the body, then according to Newton's second law of motion,
P + m.a = 0
P - m.a = 0
P × m.a = 0
P/m.a = 0
Correct Answer :
B. P - m.a = 0
Related Questions
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Coplanar concurrent forces
Coplanar non-concurrent forces
Non-coplanar concurrent forces
None of these
The wheels of a moving car possess
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Kinetic energy of translation only
Kinetic energy of rotation only
Kinetic energy of translation and rotation both
In a single threaded worm and worm wheel, the number of teeth on the worm is 50. The diameter of the effort wheel is 100 mm and that of load drum is 50 mm. The velocity ratio is
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100
200
400
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1.0 cm
1.5 cm
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A block of mass m1, placed on an inclined smooth plane is connected by a light string passing over a smooth pulley to mass m2, which moves vertically downwards as shown in the below figure. The tension in the string is 
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m1.m2/m1 + m2
m1. m2.g (1 + sin α)/(m1 + m2)
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P - Q
P / Q
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Less than
More than
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Newton's second law of motion
Principle of conservation of energy
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Equal to
Equal and opposite to
Less than
Greater than
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Newton's second law of motion
Newton's third law of motion
None of these
If the body falls freely under gravity, then the gravitational acceleration is taken as
+8.9 m/s2
-8.9 m/s2
+9.8 m/s2
-9.8 m/s2
Which of the following statement is incorrect?
A force acting in the opposite direction to the motion of the body is called force of friction
The ratio of the limiting friction to the normal reaction is called coefficient of friction
A machine whose efficiency is 100% is known as an ideal machine
The velocity ratio of a machine is the ratio of load lifted to the effort applied
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Coplanar concurrent forces
Coplanar non-concurrent forces
Like parallel forces
Unlike parallel forces
The ratio of static friction to dynamic friction is always
Equal to one
Less than one
Greater than one
None of these
When two elastic bodies collide with each other,
The two bodies will momentarily come to rest after collision
The two bodies tend to compress and deform at the surface of contact
The two bodies begin to regain their original shape
All of the above
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Same as
Twice
Thrice
Four times
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m²/kg.
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kg/m
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π/16 (D³ - d³)
π/32 (D⁴ - d⁴)
π/64 (D⁴ - d⁴)
A framed structure, as shown in the below figure, is a 
Perfect frame
Deficient frame
Redundant frame
None of the above
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MS/4
MS/5
None of these
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Joule
Watt
kg-m
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n²
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The lines of action of these forces meet in a point
The lines of action of these forces are parallel
Both (B) and (C) above
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h [(2a + b)/(a + b)]
(h/2) [(2a + b)/(a + b)]
(h/3) [(2a + b)/(a + b)]
(h/3) [(a + b)/(2a + b)]
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2π/ω
2π × ω
π/ω
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W cosθ
W secθ
W cosecθ
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Force
Work
Power
Velocity
Centre of gravity of a solid cone lies on the axis at the height
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One third of the total height above base
One-half of the total height above base
Three eighth of the total height above the base