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An athlete at the gym holds a 3.61 kg steel ball in his hand His arm is 71.8 cm long and has a mass of 4.70 kg What is the magnitude of the torque about his shoulder if he holds his arm straight out?
Wiki User
∙ 14y ago
Without detailed information about the shape and mass distribution of his arm, we have to assume that it's
homogeneous and has uniform cross section, so the center mass of his arm is at (71.8 / 2) = 35.9 cm from
the shoulder.
The torque due to the steel ball is (M G R) = (3.61 x 9.78 x 0.718) = 25.35 newton-meters. (rounded)
The torque due to the weight of his arm is (4.7 x 9.8 x 0.359) = 16.54 more newton-meters. (rounded)
The sum of the two torques is 41.89 newton-meters.
Wiki User
∙ 14y ago
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A man holds a 4.0kg steel ball in hand His arm is 70cm long and has a mass of 4.0kg What is the magnitude of the torque about his shoulder if he holds his arm straight but 50 degrees below horizontal?
29 N-m
A man holds a 4.0kg steel ball in hand His arm is 70cm long and has a mass of 4.0kg What is the magnitude of the torque about his shoulder if he holds his arm straight but 30 degrees below horizontal?
ball in hand = 4 * 9.807 = 39.228 nlever length = cos 30deg. * 0.7 = 0.6062 metrestorque = 39.228 * 0.6062 = 23.78 newton - metre.torque generated by arm = 23.78 / 2 = 11.89 newton - metre.total torque = 23.78 + 11.89 = 35.67 newton - metre
What is the difference between torque and couple?
The turning effect of a force is called torque or moment of the force. SI unit of torque is Newton-Metre. T = FL i.e Torque = Force x Moment arm A couple is formed by two unlike parallel forces of the same magnitude but not along the same line.
If a body is rotating is it necessarily bejng acted upon by an external torque?
No. Just as no force is required to keep a moving body moving in a straight lineat constant speed, no torque is required to keep a rotating body rotating at aconstant speed. External torque is present only if the body's rate of rotation ischanging.
Does torque and work are equivalent?
Torque is rotational force, while work is energy transferred between objects. For example, a screw experiences mostly torque as you twist it around its axis, while a nail experiences mostly work as it is driven straight into the wood.
A man holds a 4.0kg steel ball in hand His arm is 70cm long and has a mass of 4.0kg What is the magnitude of the torque about his shoulder if he holds his arm straight but 50 degrees below horizontal?
29 N-m
What is net torque?
Net torque is the magnitude and direction of torque that is left over when you add up the torques that are acting on an object.
A man holds a 4.0kg steel ball in hand His arm is 70cm long and has a mass of 4.0kg What is the magnitude of the torque about his shoulder if he holds his arm straight but 30 degrees below horizontal?
ball in hand = 4 * 9.807 = 39.228 nlever length = cos 30deg. * 0.7 = 0.6062 metrestorque = 39.228 * 0.6062 = 23.78 newton - metre.torque generated by arm = 23.78 / 2 = 11.89 newton - metre.total torque = 23.78 + 11.89 = 35.67 newton - metre
Deduce an expression for the torque develop by the armature of a dc motor?
he magnitude of torque depends on three quantities: First, the force applied; second, the length of the lever arm[4] connecting the axis to the point of force application; and third, the angle between the two. In symbols:whereτ is the torque vector and τ is the magnitude of the torque,r is the displacement vector (a vector from the point from which torque is measured to the point where force is applied), and r is the length (or magnitude) of the lever arm vector,F is the force vector, and F is the magnitude of the force,× denotes the cross product,θ is the angle between the force vector and the lever arm vector.
If Two forces have the same magnitude will they produce the same amount of torque when they are applied to an object?
The two forces will produce the same torque if : R1xF1 = R2xF2; r1f1sin(R1F1) = r2f2sin(R2F2). The magnitude of the forces can be the same (f1=f2=f) but their angles with the the displacement (R) can be different, r1fsin(R1F1) = r2fsin(R2F2),and the torque will be the same. Torque is the vector product of the force and displacement.
What 2 things does the moment of a force depend on?
What two factors must be known in order to calculate the moment of a force? Torque = Force * distance Torque and distance must be perpendicular to each other If not you must determine the portion of the torque that is perpendicular.
How do you calculate braking torque?
To calculate brake torque, multiply force with the distance from the point of rotation. Force is equal to the torsional reaction caused by the brakes, and is also equal in magnitude to the torque exerted by the road.
What is a linear torque curve?
A torque curve is a plot of torque produced vs RPM, as measured on a dynamometer. It usually is not linear (a straight line).
Write the universal torque equation and derive the characteristic of impedance reactance and mho relays?
soumitro paul; student of a.p.c roy polytechnic 2013answerThe universal relay torque equation isT=k1I2+k2V2+k3VIcos(a-e)+KwhereT= maximum torqueV= R.m.S magnitude of voltageI= R.M.S magnitude of currentThe spring torque will be K .a= angle between V&Ie=max torque angle
What is the energy of torque?
Static torque is basically an applied force, but applied about a centre instead of in a straight line. Dynamic torque, such as that produced by an engine, is a force translated from a straight line (piston) to a circular path (crank) and since its a force at a velocity, its rated as power.
What is inertia torque?
Inertia torque an imaginary torque, which when applied upon a rigid body, brings it in an equilibrium position. Its magnitude is equal to accelerating couple, but opposite in direction.T1 = -IαwhereI = mass moment of inertia of body andα = angular acceleration
Will the torque characteristics of all engines always be a straight line graph?
No
