A golfer hits a shot to a green that is elevated 2.50 m above the point where the ball is struck. The ball leaves the club at a speed of 17.3 m/s at an angle of 43.0˚ above the horizontal. It rises to its maximum height and then falls down to the green. Ignoring air resistance, find the speed of the ball just before it lands.

Example: The radioactive isotope decays by electron capture with a half –life of 272 days. •(a) Find the decay constant of the lifetime. •(b) If you have a radiation source containing , with activity 2.00µCi, how many radioactive nuclei does it contain? •(c) What will be the activity of this source after one year?5

The telescopes on some commercial surveillance satellites can resolve objects on the ground as small as 92 cm across (see Google Earth), and the telescopes on military surveillance satellites reportedly can resolve objects as small as 12 cm across. Assume first that object resolution is determined entirely by Rayleigh's criterion and is not degraded by turbulence in the atmosphere. Also assume that the satellites are at a typical altitude of 408 km and that the wavelength of visible light is 537 nm. What would be the required diameter of the telescope aperture for (a) 92 cm resolution and (b) 12 cm resolution? (c) Now, considering that turbulence is certain to degrade resolution and that the aperture diameter of the Hubble Space Telescope is 2.4 m, what can you say about the answer to (b), i.e. is the military surveillance resolution accomplished?

A thin-walled, hollow spherical shell of mass m and radius r starts from rest and rolls without slipping down the track shown in the figure (Figure 1) . Points A and Bare on a circular part of the track having radius R. The diameter of the shell is very small compared to h0 and R, and rolling friction is negligible. a) What is the minimum height h0 for which this shell will make a complete loop-the-loop on the circular part of the track? b) How hard does the track push on the shell at point B, which is at the same level as the center of the circle? c) Suppose that the track had no friction and the shell was released from the same height h0 you found in part (a). Would it make a complete loop-the-loop? d) In part (c), how hard does the track push on the shell at point A, the top of the circle? e) How hard did the track push on the shell at point A in part (a)?

In an experiment performed at the bottom of a very deep vertical mine shaft, a ball is tossed vertically in the air with a known initial velocity of 10.0 m/s, and the maximum height the ball reaches (measured from its launch point) is determined to be 5.101 m. Knowing the radius of the Earth, RE = 6370 km, and the gravitational acceleration at the surface of the Earth, g(0) = 9.81 m/s2, calculate the depth of the shaft.

On Apollo Moon missions, the lunar module would blast off from the Moon's surface and dock with the command module in lunar orbit. After docking, the lunar module would be jettisoned and allowed to crash back onto the lunar surface. Seismometers placed on the Moon's surface by the astronauts would then pick up the resulting seismic waves.

Find the impact speed of the lunar module, given that it is jettisoned from an orbit 170 km above the lunar surface moving with a speed of 1550 m/s

Thanks!

(1) What is the needle of a compass attracted to?

(2) What is the difference between ferromagnetic  and magnetic?

(3) In terms of electrons, what causes permanent magnetism?

(4) What is the technique in making synthetic magnets?                                                      

A uranium and iron atom reside a distance R = 58.70 nm apart. The uranium atom is singly ionized; the iron atom is doubly ionized. Calculate the distance r from the uranium atom necessary for an electron to reside in equilibrium. Ignore the insignificant gravitational attraction between the particles.

What is the magnitude of the force on the electron from the uranium ion?

In winter a lake has a 0.30m thick ice layer over 1.20m of water. A light beam from above strikes a spot on the ice, making a 29? angle with the normal.

Part A

How far horizontally from that spot does the light ray strike the lake bottom?

A small solid sphere of mass M₀, of radius R₀, and of uniform density ρ₀ is placed in a large bowl containing water. It floats and the level of the water in the dish is L. Given the information below, determine the possible effects on the water level L, (R-Rises, F-Falls, U-Unchanged), when that sphere is replaced by a new solid sphere of uniform density.

The new sphere has radius R > R₀ and density ρ < ρ₀

The new sphere has radius R = R₀ and mass M < M₀

The new sphere has mass M < M₀ and density ρ = ρ₀

The new sphere has density ρ = ρ₀ and mass M > M₀

The new sphere has mass M = M₀ and density ρ > ρ₀

The new sphere has mass M = M₀ and density ρ < ρ₀

A rock is thrown downward from a tower with an initial speed of 32.2 m/s. If it hits the ground in under 2 seconds how high is the tower?

A 90 kg student jumps off a bridge with a 12-m-long bungee cord tied to his feet. The massless bungee cord has a spring constant of 420 N/m. You can assume that the bungee cord exerts no force until it begins to stretch.

How far below the bridge is the student's lowest point?

How far below the bridge is the student's resting position after the oscillations have been fully damped?