The same constant force is used to accelerate two caritos of equal masses, initially at rest on a horizontal surface without friction. The force is applied to cart A for twice as long as the duration applied to cart B. The work done on body A is WA; and the one performed on B is WB. Which of the following statements is correct? a) WA = WB b) WA = WB c) WA = 2 WB d) WA = 4 WB e) WB = 2WA

A 5 kg ball is shot straight up with an initial speed of 20 m/s . When the ball reaches height 10 m, the balls speed is 10 m/s. The work done on the ball by the force of air resistance , up to this height is equal to? A- 260J B- 490J C- 500 J D- 510J E- 750J

Figure 9 shows four situations in which a force F is applied to an object resulting in displacement Ař. The force has the same magnitude in all four cases, but points in different directions. The displacement is exactly the same in all four cases. Which of the following choices correctly ranks the work done by the force on the object? a) W. < Wa < Wa < Wp b) Wa < Wc < W, < Wa c) Wa < Wc < Wa < Wp d) Wa < W, < Wa < Wc e) Wh < Wa < Wa < Wc Ar Δ b Ar Ar Figure 9

A 1350-kg car is traveling with an initial speed of 25.0 m/s. Determine the car's speed after -2.20 × 10° J of net work is done on the car. X m/s

1. Boxing gloves are padded to lessen the force of a blow. The glove and face compress 7.5000 cm during a blow in which the 7.0000-kg arm and glove are brought to rest from an initial speed of 10.0000 m/s. ▬▬ - Think & Prepare 1. Make note of what's given and what's unknown. Relate known quantities to symbols. 2. Draw a labeled sketch if possible. 3. Identify the physics principle and approach. Write down relevant equations symbolically. Simplify if possible. 4. Insert numerical quantities to solve for unknowns. 5. Does the answer make sense? % (a) Calculate the change in kinetic energy of the glove and arm. AKE = (b) Where does this energy go? O Search 5 O into doing work against the force exerted by the face against the glove O into doing work against gravity O into the potential energy of the face O into the potential energy of the glove and arm T 4- 6 Y 17 + & J 7 90 8 * 8 U I 이 144 ( 9 110 DII O E DDI I P 2 { 4 ( ← backs

A student could either pull or push, at an angle of 30⁰⁰ from the horizontal, a 60 kgkg crate on a horizontal surface, where the coefficient of kinetic friction between the crate and surface is 0.21. The crate is to be moved a horizontal distance of 25 mm A) Compared with pushing, pulling requires the student to do more, less, or the same work. B) Calculate the minimum work required for both pulling and pushing. Express your answers using two significant figures separated by a comma. Answer must be in J Wpulling, Wpushing =

A 6.50 kg box slides 4) from the top of a ramp to the bottom at a constant speed, as shown in the diagram. constant v= 1.50 m/s h= 1.85 m 0= 28.2° a) How much work is done on the box by the frictional force? b) How much work is done on the box by gravity? c) How much work is done on the box by the normal force? d) What is the coefficient of kinetic friction between the box and the ramp?

An elevator suspended by cables ascends, with constant speed, during a certain time interval. The total work done on the elevator in this time interval is: Choose an option: a) missing datab) Same as pulling work on cablesc) Nulld) Positivee) Negativef) Equal to the work of gravitational force

An 8 kg sled is at rest on a horizontal road. The coefficient of kinetic friction between the sled and the road is 0.4. The sled is pulled a distance of 3 m by a force of 40 N applied to the sled at an angle of 30 degree.a) Find the work done by the applied force.b) Find the work done by friction. c) Find the change in kinetic energy of the sled.d) Find the speed of the sled after it has traveled 3 m.

A force of 100N acts on a block at an angle of 53° with respect to the horizontal, as shown. As the block moves through a displacement of 4 m to the left, the work done on the block by the force is A) +320 Nm B) +240 Nm F C) zero Ax D) -240 Nm E) -3200 Nm O A O D O E