A bolt gun has a spring of spring constant k = 14 N/m which is used to fire a bolt of mass m. The bolt leaves the gun at a speed of v = 5.8 m/s after the spring is compressed 1 cm. What is the weight, Fg in Newtons, of the bolt?  What is the bolt’s speed when it hits the floor vf, in m/s, if it is fired horizontally at a height of h = 2 meters?

Figure P7.44 45. Review. Two constant forces act on an object of mass m = QIC 5.00 kg moving in the xy plane as shown in Figure P7.45. Force F, is 25.0 N at 35.0°, and force F, is 42.0 N at 150°. At time t = 0, the object is at the origin and has velocity (4.00î + 2.50j) m/s. (a) Express the two forces in unit-vector notation. Use unit-vector notation for your other answers. (b) Find the total force exerted on the object. (c) Find the object's acceleration. Now, considering the instant t = 3.00 s, find (d) velocity, (e) its position, its kinetic energy the object's (f) from mv, and (g) its F2 F kinetic from 150° energy mu + EF · A. (h) What conclusion can you draw by comparing the answers to parts (f) and (g)? 35.0° m Figure P7.45

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A proton (mass m = 1.67 × 10-27 kg) is being accelerated along a straight line at 9.80 × 101¹1 m/s² in a machine. If the proton has an initial speed of 5.40 × 104 m/s and travels 3.80 cm, what then is (a) its speed and (b) the increase in its kinetic energy?

A massless spring with spring constant k = 400N/m is placed on a platform which is inclined with angle 0 above the horizontal. A block of mass 1kg is attached to the spring and the spring is compressed by 20cm as shown in the figure. There is no friction between the block and the platform. Find the speed of the block as it travels a distance of 30cm along the platform after it is released. (Take g = 10m/s² and sin 0 = 2/3). m = Select one: О а. 3 m/s O b. 1 m/s k m O c. 5 /ms www O d. 4 m/s О е. 2 m/s

In the figure here, two children are playing a game in which they try to hit a small box on the floor with a marble fired from a spring- loaded gun that is mounted on a table. The target box is horizontal distance D = 2.18 m from the edge of the table. Bobby compresses the spring 1.18 cm, but the center of the marble falls 25.6 cm short of the center of the box. How far should Rhoda compress the spring to score a direct hit? Assume that neither the spring nor the ball encounters friction in the gun. 00000 Number i Unit

The massless spring of a spring gun has a force constant k = below.) How much was the spring compressed initially? (Find d, in meters.) 0.06 N/cm. When the gun is aimed vertically, a 29 g projectile is shot to a height of 5.0 m above the end of the expanded spring. (See 5.0 m d = ? NNNNNNNN ONNNNNNNM