All categories

3 years ago

A ball is thrown vertically upward with a speed of 12.0 m/s. ( a. How high does it rise?

1 answer:

5 0

It rises till all of its Kinetic energy is converted into potential energy.

so, mgh=(1/2)m(v^2)

so, h=(v^2)/2g = 12*12/(2*9.81)=7.34 m

You might be interested in

A carpenter is driving a 15.0-g steel nail into a board. His 1.00-kg hammer is moving at 8.50 m/s when it strikes the nail. Half

bekas [8.4K]

Answer: The increase in temperature of the nail after the three blows is 8.0636 Kelvins. The correct option is (d).

Explanation:

Kinetic energy of the hammer ,K.E.=

$\frac{1}{2}mv^2=\frac{1}{2}1.00 kg\times (8.50 m/s)^2=36.125 J$

Half of the kinetic energy of the hammer is transformed into heat in the nail.

Energy transferred to the nail in one blow =

$\frac{1}{2}K.E.=\frac{1}{2}\times 36.125 J=18.0625 J$

Total energy transferred after 3 blows,Q = $3\times 18.0625 J=54.1875 J$

Mass of the nail = 15 g = 0.015 kg

Change in temperature = $\Delta T$

Specif heat of the steel = c = 448 J/kg K

$Q=mc\Delta T$

$54.1875 J=0.015 kg\times 448 J/kg K\times \Delta T$

$\Delta T=8.0636 K\approx 8.1 K$

The increase in temperature of the nail after the three blows is 8.1 Kelvins.Hence, correct option is (d).

4 0

3 years ago

A 20-kg cart travels at 20 m/s in a circle with a radius of 20 m. What is the centripetal force?

Vlad1618 [11]

Centripetal force = (mass) x (speed)² / (radius)

   = (20 kg) x (20 m/s)² / (20 m)

   = (20 x 20 / 20) (kg-meter/sec²)

   = 20 newtons

5 0

3 years ago

Read 2 more answers

Can someone help me with physics;((

vladimir2022 [97]

Answer: vf= 51 m/s and d= 112 m

Explanation: solution attached

4 0

3 years ago

Plzzz help me will mark brilliant

Setler79 [48]

Answer:

i hope it helped U

stay safe stay happy

3 0

3 years ago

75 pts!

jasenka [17]

again CORRECT ans is 4) light strikes the grooves → different wavelengths of light bend at different angles → diffracted wavelengths reach the eyes → the eyes see different colors.

moderator - plz review the ans as u deleted my right ans n approved the wrong ans :(

6 0

3 years ago

Read 2 more answers