FORCES IN ONE DIMENSION

Transcription

1 Suppleental Proble ORCES I OE DIMESIO 1. You and your bike have a cobined a of 80 k. How uch brakin force ha to be applied to low you fro a velocity of 5 / to a coplete top in? vf vi 0.0 / 5.0 / a t t f.5 / a i 80k (.5 / ) 00. Before openin hi parachute, a ky diver with a a of 90.0 k experience an upward force fro air reitance of 150. a. What force i actin on the ky diver? ravity 90.0 k 9.8 /k 880 downward air reitance ravity 150 ( 880 ) 73 Ν 730 downward b. What i the ky diver acceleration? a k 8.1 / 8.1 / downward 3. A lare helicopter i ued to a heat pup to the roof of a new buildin. The a of the helicopter i k and the a of the heat pup i 1500 k. a. How uch force ut the air exert on the helicopter to the heat pup with an acceleration of 1.5 /? Teacher Support overcoe ravity a ( k) (1.5 / ) ( k )(9.8 /k) upward b. Two chain connected to the load each can withtand a tenion of 15,000. Can the load be afely ed at 1.5 /? load overcoe ravity a ( k) (1.5 ) ( k) (9.8 K) The load can be afely ed becaue the total force on the chain i le than their cobined capability of In a lab experient, you attach a.0-k weiht to a prin. You the and weiht with a contant readin of.5. a. What i the value and direction of the acceleration on the weiht? ravity.5 (.0 k) (9.8 k).9 upward a.9.0 k 1.4 / b. How far do you the weiht in the firt.0- interval? 1 x fxivit at 0 (0 /) (.0 ) 1 (1.4 / )(.0 ).8 Chapter 4 orce in One Dienion 3 Copyriht Glencoe/McGraw-Hill, a diviion of The McGraw-Hill Copanie, Inc.

2 Suppleental Proble Teacher Support continued 5. A a lare jet flie at a contant altitude, it enine produce a forward thrut of The a of the plane i k. a. What i the forward acceleration of the plane, inorin air reitance? a a k 3. / b. How uch upward force ut the air exert on the plane when it i flyin horizontally? Becaue the plane i not chanin altitude, 0, o ravity ravity (.6105 k)( 9.8 / k) Two ae are tied to a rope on a pulley, a hown below. a. When the yte i releaed fro thi poition, what i the acceleration of the.0-k a? -lare -all lare all (.00 k)(9.8 /k) (0.80 k)(9.8 /k) 11.8 downward a k 4. / downward b. How lon doe it take for the.0-k a to fall to the floor? 1 Solve x f xi vit at for t while x i 0, v i 0 / t x a ()(1.5 ) 4. / A an i tandin on a inide an airplane. When the airplane i travelin horizontally (in other word, the vertical acceleration of the plane i zero) the read What i the vertical acceleration of the plane in each of the followin ituation? a. When the read a a a (9.8 /k)( ) / Chapter 4 orce in One Dienion Copyriht Glencoe/McGraw-Hill, a diviion of The McGraw-Hill Copanie, Inc. 4

3 Suppleental Proble Teacher Support continued b. When the read a a a (9.8 /k)( ) / 8. An airboat lide acro the urface of the water on a cuhion of air. Perfor the followin calculation for a boat in which the a of the boat and paener i 450 k. a. If there i no friction, how uch force ut the propeller fan exert on the air to accelerate the boat at 5.0 /? a (450 k)(5.00 / ).103 b. What i the upward force exerted by the air cuhion on the boat? ravity (450k) ( 9.80 / ) A olf ball with a a of 45 i truck by a club, leavin the tee with a peed of k/h. The period of acceleration wa a. What i the averae acceleration on the ball a it wa truck (in / )? vf vi a, where vi 0 k/h t h (1.810 k/h) 1 K 3600 a 1 (0.50 ) / / b. What i the force exerted on the club? a 1 k (45 ) 5 ( / ) c. What i the force exerted on the club by the ball? ball club A packae of intruent i attached to a heliu-filled weather balloon that exert an upward force of 45. a. If the intruent packae weih 10.0 k, will the balloon be able to it? a a k 4.5 / The balloon cannot the packae becaue the upward acceleration i le than the downward acceleration of ravity, 9.8 /. Alternative calculation: ravity (10.0 k)(9.8 /K) 98.0, which exceed the upward force b. What i the upward acceleration if the intruent weih.0 k? Chapter 4 orce in One Dienion 5 Copyriht Glencoe/McGraw-Hill, a diviion of The McGraw-Hill Copanie, Inc.

4 Suppleental Proble Teacher Support continued ravity a 45 (.0 k) (9.8 /K) 5.4 a k 13 / upward 11. A 1-k block it on a table. A 10.0-k block it on top of the 1-k block. If there i nothin on top of the 10.0-k block, what i the force that the table exert on the 1-k block? table block 1 block (1 k)(9.8 /k) (10.0 k)(9.8 /k) 0 1. A 9.7-k box experience a force of 41 while it i bein ed. What i the acceleration of the box? a a k 4. / 13. A rope can withtand of tenion. If the rope i bein ued to pull a 10.0-k packae acro a frictionle urface, what i the reatet acceleration that will not break the rope? a a k / 14. A k weiht i attached to a prin. ind the readin on the for each of the followin ituation. a. When the i not ovin. (0.100 k)(9.8 /k) 0.98 b. When the accelerate at.4 / in the horizontal direction. The vertical coponent of the acceleration i zero, o the readin on the i calculated the ae way a when the i not ovin. (0.100 k)(9.8 /k ) A penny i dropped fro the top of a tall tower. The tower, however, i not located on Earth. The penny ha a a of.5 and experience a ravitational force of a. What i the ravitational field on thi pla? a k 11 / b. After 1.00, the penny ha a velocity of 10.1 /. Auin the force exerted on the penny by air reitance i unifor and independent of peed, what i the anitude of the force of air reitance on the penny? a ( ) a a a a a, where v t v t Chapter 4 orce in One Dienion Copyriht Glencoe/McGraw-Hill, a diviion of The McGraw-Hill Copanie, Inc. 6

5 Suppleental Proble Teacher Support continued vf vi t 0.08 (0.005 k) 10.1 / 0.0 / The air reitance i in the oppoite direction fro the force of ravity and the penny otion, a it hould be. 16. The cobined a of a led and it rider i 46.4 k. The led i pulled acro a frozen lake o that the force of friction between the led and the ice i very all. Auin that friction between the led and the ice i neliible, what force i required to accelerate the led at 3.45 /? a (46.4 k)(3.45 / ) Chapter 4 orce in One Dienion 7 Copyriht Glencoe/McGraw-Hill, a diviion of The McGraw-Hill Copanie, Inc.