Physics Answers

If the spring constant is 30 N/m and a spring is stretched by 0.3m, how much force has

been applied

Two men, of mass 100 kg each, stand on a cart of mass 300 kg. The cart can roll with negligible friction along a north-south track, and everything is initially at rest. One man runs towards the north and jumps off the cart at a speed of 5.0 m/s, relative to the cart. After he has jumped, the second man runs towards the south and jumps off the cart, again with a speed of 5.0 m/s relative to the cart.

Calculate the speed and direction of the cart after both men have jumped off. 

A flow of 834 cfs is conveyed in a 10-ft-wide rectangular channel at a depth of 6.0 ft. What is the specific energy of the channel? Is this flow subcritical or supercritical? If n = 0.014, what channel slope must be provided to produce a uniform flow at this depth? Check your solution using appropriate computer software.

1.Water flows at 750 m³/s down a rectangular channel made of finished concrete. The channel has a width of 4 m and a downward slope of 0.0002, and the water depth is 1.5 m at the control section A. Determine the distance x from A to where the depth becomes 1.25 m. Use delta y = 0.05 m and plot the surface profile. Take n = 0.012.

2. The rectangular channel is fitted with a 60 degrees or triangular weir plate. If the upstream depth of the water is 2 m. and the bottom of the weir plate is 1.6 m from the bottom of the channel. determine the volumetric flow of water prang over the weir. Take C_d = 0.72. 

1.The rectangular channel has a width of 4 m and transports water at 1.20(10⁶) liters/min. If the elevation of the bed drops by 0.4 ft, determine the depth y₂ after the depression.

2. A flow of 60 m³/s passes under the sluice gate. If y₁ = 6 in. determine the depth y₂ and the type of flow downstream. Also, what is the maximum volumetric flow that can pass through the gate?

1.A large tank contains water having a depth of 1.5 m. lf the tank is on an elevator that is descending, determine the horizontal speed of a wave created on its surface if the rate of descent is (a) constant at 6 m/s. (b) accelerated at 1.5 m/s2. (c) accelerated at 9.81 m/s2.

2.. Water flows at 840(103) liters/min through a rectangular channel having a width of 3 m. If yA = 1 m, show that yB = 1.25 m is possible. What is the necessary increase in elevation h of the channel bed to create this depth?

1. A cue ball on a pool table is hit with the cue stick in one corner of the table and rolls to the opposite corner.  The mass of the ball is 0.17 kg and it starts rolling at a speed of 3.6 m/s.  By the time it reaches the opposite corner of the table, the ball has a kinetic energy of 0.65 J.  Determine the following: (a) the initial kinetic energy, (b) the speed of the ball at the opposite corner of the table, and (c) the work done by friction as the ball rolls from one corner to the other.

(a) A sphere has a surface uniformly charged with 1.00 C. At what distance from its center is the potential 5.00 MV? (b) What does your answer imply about the practical aspect of isolating such a large charge?

1. Ball thrown at 45° with intial velocity of 25m/s.

Find the

A. Initial velocity

B. Final velocity

C. Acceleration (m/s²)

D. Time ( s )

E. Distance ( m )

1. Ball thrown at 30° with intial velocity of 20m/s.

Find the

A. Initial velocity

B. Final velocity

C. Acceleration (m/s²)

D. Time ( s )

E. Distance ( m )