Center of Mass

A large cannon is mounted on a cart with frictionless wheels that is initially at rest on a horizontal surface. The cannon fires a large cannonball to the right with a speed v_cannonball which is then caught by a trap firmly attached to the cart. What is the final speed of the cannon-cart-cannonball system?

• v>v_cannonball to the left

• v>v_cannonball to the right

• 0

• v<v_cannonball to the left

• v<v_cannonball to the right

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

A cannon is mounted on a cart, and carrying a cannonball. The total mass of the cart, cannon, and ball is M, and the cart is rolling with no friction at a velocity v in the positive x-direction as shown above. The ball, of mass m, is fired with a velocity of vball in the positive x direction. What is the velocity of the cart and cannon after the ball is fired?

• (Mv-mv_ball)/(M-m_ball)

• (Mv-mv_ball)/M

• (v-mv_ball)/m_ball

• (Mv+mv_ball)/(M-m_ball)

• (-Mv-mv_ball)/(M+m_ball)

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

Two point masses of 3.6 kg & 7.8 kg are located 0.5 m & 3.1 m from the origin along the x-axis respectively. What is their center of mass?

• 0.32 m

• 1.32 m

• 2.28 m

• 3.16 m

Three point masses are attached to a massless rigid rod. The first mass (1 kg) is located at 0.5 m, while the second mass (2 kg) is located at 1 m, & the last mass (3 kg) is located at 1.5 m. What is the center of mass of the system?

• 1.2 m

• 1.3 m

• 2.3 m

• 2.5 m

Three point masses are attached to a massless rigid rod. The first mass (2 kg) is located at 2 m, while the second mass (3 kg) is located at 3 m, & the last mass (4 kg) is located at 4 m. What is the center of mass of the system?

• 3.2 m

• 3.3 m

• 3.6 m

• 64 m

A 52-kg woman and a 86-kg man sit on a seesaw, 3 m long. Where is their center of mass?

• 0.75 m

• 1.87 m

• 32.4 m

• 46 m

Tags

NGSS.MS-PS2-4

A 49.5-kg woman and a 83.1-kg man sit on a seesaw, 2.6 m long. Where is their center of mass?

• 0.6 m

• 1.6 m

• 2 m

• 51 m

Tags

NGSS.MS-PS2-4

Two point masses of 2 kg & 4 kg are located 2 m & 4 m from the origin along the x-axis respectively. What is their center of mass?

• 0.3 m

• 0.375 m

• 2.6 m

• 3.3 m

Two objects of masses 2 & 5 kg are hung from the ends of a stick that is 70 cm long & has marks every 10 cm. If the mass of the stick is negligible, at which point should a cord be attached if a stick is to remain horizontal when suspended from the cord?

• 20

• 30

• 40

• 50

Tags

NGSS.MS-PS2-2

Two point masses of 5 kg and 10 kg are located 1 m and 4 m from the origin along the x-axis respectively. What is their center of mass?

• 1.5 m

• 2.5 m

• 3.5 m

• 4.5 m