What is Singularity?
Definition In physics, a singularity is a point in spacetime where gravity becomes infinitely strong and the usual laws of physics no longer work. It’s… Read More »What is Singularity?
What is an Event Horizon?
Definition An event horizon is the invisible boundary around a black hole beyond which nothing — not even light — can escape. It’s often called… Read More »What is an Event Horizon?
In fig 23.43 AB represents a uniform beam of weight 150 N which rests with the end B on a rough plane inclined
Question In fig 23.43, AB represents a uniform beam of weight 150 N which rests with the end B on a rough plane inclined at… Read More »In fig 23.43 AB represents a uniform beam of weight 150 N which rests with the end B on a rough plane inclined
Find the value of W and the tensions in the three strings in fig 23.32. CF and DE are horizontal.
Question Find the value of W and the tensions in the three strings in fig 23.32. CF and DE are horizontal. Solution Here is how… Read More »Find the value of W and the tensions in the three strings in fig 23.32. CF and DE are horizontal.
Find the tensions in the three strings and the weight W in fig 23.31
Question Find the tensions in the three strings and the weight W in fig 23.31. AB is horizontal. (Draw an accurate scale figure first. Draw… Read More »Find the tensions in the three strings and the weight W in fig 23.31
On a 20-mile bike ride you ride the first 10 miles at an average speed of 8 mi/h.
Question On a 20-mile bike ride, you ride the first 10 miles at an average speed of 8 mi/h. (a) What must your average speed… Read More »On a 20-mile bike ride you ride the first 10 miles at an average speed of 8 mi/h.
If an a.c is represented by I = IoSinωt. Calculate the instantaneous value
Question IF AN A•C IS REPRESENTED BY I = IoSinωt. CALCULATE THE INSTANTANEOUS VALUE OF SUCH A CURRENT, IF IN A CIRCUIT IT HAS A… Read More »If an a.c is represented by I = IoSinωt. Calculate the instantaneous value
The current through a resistor in an a.c circuit is given as 2sinωt
Question The current through a resistor in an a.c circuit is given as 2sinωt. Determine the d.c equivalent of the current. Solution The equation given… Read More »The current through a resistor in an a.c circuit is given as 2sinωt
Calculate the peak voltage of a mains supply of r.m.s value 220V
Question Calculate the peak voltage of a mains supply of r.m.s value 220V. Solution Root mean square of the voltage is Vrms = 220V Peak… Read More »Calculate the peak voltage of a mains supply of r.m.s value 220V
The current I in an a.c circuit is given by the equation I = 30sin100πt
Question The current, I in an a.c circuit is given by the equation I = 30sin100πt, where t is the time in seconds. Deduce the… Read More »The current I in an a.c circuit is given by the equation I = 30sin100πt
A robotic vehicle or rover is exploring the surface of Mars
Question A robotic vehicle, or rover, is exploring the surface of Mars. The landing craft is the origin of the coordinates, and the surrounding Martian… Read More »A robotic vehicle or rover is exploring the surface of Mars
Use Eqs. (2.17) and (2.18) to find v_x, and x as functions of time in the case in which the acceleration is constant
Question Use Eqs. (2.17) where vx = vox + axt and (2.18) where x = xo + ∫vxdt to find vx, and x as functions… Read More »Use Eqs. (2.17) and (2.18) to find v_x, and x as functions of time in the case in which the acceleration is constant
Sally is driving along a straight highway in her classic 1965 Mustang. At time
Question Sally is driving along a straight highway in her classic 1965 Mustang. At time t = 0, Sally is moving at 10 m/s in… Read More »Sally is driving along a straight highway in her classic 1965 Mustang. At time
Calculating the Scalar Product Using Components
Calculating the Scalar Product Using Components We can calculate the scalar product Ä • B directly if we know the x-, y-, and 2-components of… Read More »Calculating the Scalar Product Using Components
Find the scalar product Ä – B of the two vectors in Fig. 1.27.
Question Find the scalar product Ä – B of the two vectors in Fig. 1.27. The magnitudes of the vectors are A = 4.00 and… Read More »Find the scalar product Ä – B of the two vectors in Fig. 1.27.