*Let north and east as positive direction.
1. a = +30 km / 2 hr
a = +15 km/hr
2. a = +45 km / 3 hr
a = +15 km/hr
3. a = -30 km / 1.5 hr
a = -20 km/hr
4. a = -25 km / 0.5 hr
a = -50 km/hr
speed = (15+15+20+50) / 4
= 25 km/hr
velocity:
(horizontal): (+15-50)= -35 km/hr
(vertical): (+15-20)= -5km/hr
v = sqrt(35^2 + 5^2)
v = 35.36 km/hr
Answer:
28 J
Explanation:
Mechanical energy is the sum of kinetic and potential energy in an object that is used to do work. In other words, it is energy in an object due to its motion or position, or both.
In physics, mechanical energy (Emech) is the energy associated with the motion and position of an object usually in some force field.
Therefore:
ME = KE + PE = 25 + 3 = 28 J
<span>C. Travel toward the beach faster</span>
Answer:
Fricción.
Explicación:
Caminando con otro compañero al mismo tiempo y al mismo ritmo, el movimiento se produce debido a la fricción del suelo y la suela de los zapatos porque la fricción es la fuerza que ayuda en el movimiento de los objetos de un lugar a otro. Si no hay fricción entre el suelo y la suela de los zapatos, no podemos dar un paso por lo que podemos decir que la fricción nos mueve hacia adelante.
heat released Q = 749 joules
heat of fusion of silver L = 109 J/g
Here phase of silver is changing from liquid to solid
so temperature will remain same
all heat will be released due to its phase change
and in this case we use Q=mL
where m is the mass of silver in gram
Q= mL
749 = m * 109
m = 749/109
m = 6.87 gram
