Physics Answers

Respectfully, the answer provided to my question #274901 does not address the question I asked.

Can we say, from special relativity, that since the accelerating force was applied to object B, that the clock in B will, in reality, tick more slowly than the clock in A?

Please disregard the effects of gravity for this scenario.

Thank you.

Two spherical objects have equal masses and experience a gravitational force of 25 N towards one another. Their centers are 36 cm apart. Determine each of their masses.

An object has a positive velocity and a decreasing kinetic energy, which of the following could apply to this situation?

(a) It has a positive position moving toward the origin under a negative net force.

(b) It has a negative position moving away from the origin under a negative net force.

(c) It has a negative position moving toward the origin with a positive acceleration.

(d) It has a positive position moving away from the origin and speeding up.

(e) It has a negative position moving toward the origin and slowing down.

Which of the following is ALWAYS true?

(a) An object with a positive net force acting on it has an increasing kinetic energy.

(b) An object with a constant non-zero net force has a changing kinetic energy.

(c) If an object has a constant kinetic energy, its velocity is also constant.

(d) If an object has a constant kinetic energy the net force acting on it is zero.

(e) If an object's kinetic energy is constant, then the object's acceleration is zero.

A 2.6 kg block, in contact with a 90 N/m spring compressed by 2 m, is moving at 4.5 m/s along a ledge 5 m above the surface of the Earth, which is the zero reference level. What is the total energy of the block, as the system?

(a) 127.4 J (b) 180 J (c) 153.7 J (d) 333.7 J (e) 26.3 J

A 44 kg block is moving at 6.5 m/s at the bottom of a rough 22-degree incline. If the coefficient of friction on the incline is 0.16, what distance up along the incline does the block travel?

(a) 33.7 cm (b) 76.5 cm (c) 14.6 m (d) 80.8 cm (e) 145 cm

A 7.4 kg cart initially moving at 3 m/s is pushed for 1.4 m by a net force of 22 N. How fast will the cart be moving when the force stops acting?

(a) 2.9 m/s (b) 6.8 m/s (c) 7.5 m/s (d) 4.2 m/s (e) 3.9 m/s

What is the angular acceleration of a ball that starts at rest and increases its angular velocity uniformly to rad/s in 10 s?

What is the angular velocity of an object traveling in a circle of radius 0.75 m with a linear speed of 3.5 m/s?

Mark bought a pizza of a radius of 0.5 m. A fly lands on the pizza and walks around the edge for a distance of 80 cm. Calculate the angular displacement of the fly?

Water at room temperature flows with a constant speed of 8.00 m/s through a nozzle with a square cross section, as shown in the figure. Water enters the nozzle at the point A and exits the nozzle at point B. The length of the sides of the square cross section at A and B are 50.0 cm and 20.0 cm, respectively.

a. What is the volume flow rate at the exit?

b. What is the acceleration at the exit? The length of the nozzle is 2.00 m.

c. If the volume flow rate through the nozzle is increased to 6.00 m3/s, what is the acceleration of the fluid at the exit?

A block of cherry wood that is 20.0 cm long, 10.0 cm wide, and 2.00 cm thick has a density of 800. kg/m3. What is the volume of a piece of iron that, if glued to the bottom of the block, makes the block float in water with its top just at the surface of the water? The density of iron is 7860 kg/m3, and the density of water is 1000. kg/m3.

13. An automobile accelerates uniformly at 8 m/s2. If the force causing the acceleration is 6000 N, what is the mass of the automobile?

14. Find the force required to increase the velocity of a 1.2 kg mass from 3 m/s to 8 m/s over a period of 4 seconds.